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Matarèse BFE, Rusin A, Seymour C, Mothersill C. Quantum Biology and the Potential Role of Entanglement and Tunneling in Non-Targeted Effects of Ionizing Radiation: A Review and Proposed Model. Int J Mol Sci 2023; 24:16464. [PMID: 38003655 PMCID: PMC10671017 DOI: 10.3390/ijms242216464] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Revised: 11/01/2023] [Accepted: 11/13/2023] [Indexed: 11/26/2023] Open
Abstract
It is well established that cells, tissues, and organisms exposed to low doses of ionizing radiation can induce effects in non-irradiated neighbors (non-targeted effects or NTE), but the mechanisms remain unclear. This is especially true of the initial steps leading to the release of signaling molecules contained in exosomes. Voltage-gated ion channels, photon emissions, and calcium fluxes are all involved but the precise sequence of events is not yet known. We identified what may be a quantum entanglement type of effect and this prompted us to consider whether aspects of quantum biology such as tunneling and entanglement may underlie the initial events leading to NTE. We review the field where it may be relevant to ionizing radiation processes. These include NTE, low-dose hyper-radiosensitivity, hormesis, and the adaptive response. Finally, we present a possible quantum biological-based model for NTE.
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Affiliation(s)
- Bruno F. E. Matarèse
- Department of Haematology, University of Cambridge, Cambridge CB2 1TN, UK;
- Department of Physics, University of Cambridge, Cambridge CB2 1TN, UK
| | - Andrej Rusin
- Department of Biology, McMaster University, Hamilton, ON L8S 4L8, Canada; (A.R.); (C.S.)
| | - Colin Seymour
- Department of Biology, McMaster University, Hamilton, ON L8S 4L8, Canada; (A.R.); (C.S.)
| | - Carmel Mothersill
- Department of Biology, McMaster University, Hamilton, ON L8S 4L8, Canada; (A.R.); (C.S.)
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2
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Schrinski B, Yang Y, von Lüpke U, Bild M, Chu Y, Hornberger K, Nimmrichter S, Fadel M. Macroscopic Quantum Test with Bulk Acoustic Wave Resonators. PHYSICAL REVIEW LETTERS 2023; 130:133604. [PMID: 37067306 DOI: 10.1103/physrevlett.130.133604] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Accepted: 02/15/2023] [Indexed: 06/19/2023]
Abstract
Recently, solid-state mechanical resonators have become a platform for demonstrating nonclassical behavior of systems involving a truly macroscopic number of particles. Here, we perform the most macroscopic quantum test in a mechanical resonator to date, which probes the validity of quantum mechanics by ruling out a classical description at the microgram mass scale. This is done by a direct measurement of the Wigner function of a high-overtone bulk acoustic wave resonator mode, monitoring the gradual decay of negativities over tens of microseconds. While the obtained macroscopicity of μ=11.3 is on par with state-of-the-art atom interferometers, future improvements of mode geometry and coherence times could test the quantum superposition principle at unprecedented scales and also place more stringent bounds on spontaneous collapse models.
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Affiliation(s)
- Björn Schrinski
- Center for Hybrid Quantum Networks (Hy-Q), Niels Bohr Institute, University of Copenhagen, Blegdamsvej 17, DK-2100 Copenhagen, Denmark
| | - Yu Yang
- Department of Physics, ETH Zürich, 8093 Zürich, Switzerland
| | - Uwe von Lüpke
- Department of Physics, ETH Zürich, 8093 Zürich, Switzerland
| | - Marius Bild
- Department of Physics, ETH Zürich, 8093 Zürich, Switzerland
| | - Yiwen Chu
- Department of Physics, ETH Zürich, 8093 Zürich, Switzerland
| | - Klaus Hornberger
- University of Duisburg-Essen, Faculty of Physics, Lotharstraße 1, 47048 Duisburg, Germany
| | - Stefan Nimmrichter
- Naturwissenschaftlich-Technische Fakultät, Universität Siegen, Walter-Flex-Straße 3, 57068 Siegen, Germany
| | - Matteo Fadel
- Department of Physics, ETH Zürich, 8093 Zürich, Switzerland
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3
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Piscicchia K, Porcelli A, Bassi A, Bazzi M, Bragadireanu M, Cargnelli M, Clozza A, De Paolis L, Del Grande R, Derakhshani M, Lajos D, Donadi S, Guaraldo C, Iliescu M, Laubenstein M, Manti S, Marton J, Miliucci M, Napolitano F, Scordo A, Sgaramella F, Sirghi DL, Sirghi F, Vazquez Doce O, Zmeskal J, Curceanu C. A Novel Approach to Parameter Determination of the Continuous Spontaneous Localization Collapse Model. ENTROPY (BASEL, SWITZERLAND) 2023; 25:295. [PMID: 36832661 PMCID: PMC9955578 DOI: 10.3390/e25020295] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 01/29/2023] [Accepted: 01/29/2023] [Indexed: 06/18/2023]
Abstract
Models of dynamical wave function collapse consistently describe the breakdown of the quantum superposition with the growing mass of the system by introducing non-linear and stochastic modifications to the standard Schrödinger dynamics. Among them, Continuous Spontaneous Localization (CSL) was extensively investigated both theoretically and experimentally. Measurable consequences of the collapse phenomenon depend on different combinations of the phenomenological parameters of the model-the strength λ and the correlation length rC-and have led, so far, to the exclusion of regions of the admissible (λ-rC) parameters space. We developed a novel approach to disentangle the λ and rC probability density functions, which discloses a more profound statistical insight.
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Affiliation(s)
- Kristian Piscicchia
- Centro Ricerche Enrico Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, 00184 Rome, Italy
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Alessio Porcelli
- Centro Ricerche Enrico Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, 00184 Rome, Italy
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Angelo Bassi
- Department of Physics, University of Trieste, 34127 Trieste, Italy
- Section of Trieste, Istituto Nazionale di Fisica Nucleare, 34149 Trieste, Italy
| | | | - Mario Bragadireanu
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
| | - Michael Cargnelli
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Science, 1030 Wien, Austria
| | - Alberto Clozza
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Luca De Paolis
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Raffaele Del Grande
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- Excellence Cluster Universe, Technische Universität München, 80333 München, Germany
| | | | - Diósi Lajos
- Department of Physics of Complex Systems, Eötvös Loránd University, 1117 Budapest, Hungary
- Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, 1525 Budapest, Hungary
| | - Sandro Donadi
- Section of Trieste, Istituto Nazionale di Fisica Nucleare, 34149 Trieste, Italy
| | - Carlo Guaraldo
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Mihai Iliescu
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | | | - Simone Manti
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | - Johann Marton
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Science, 1030 Wien, Austria
| | - Marco Miliucci
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
| | | | | | | | - Diana Laura Sirghi
- Centro Ricerche Enrico Fermi—Museo Storico della Fisica e Centro Studi e Ricerche “Enrico Fermi”, 00184 Rome, Italy
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
| | - Florin Sirghi
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
| | | | - Johann Zmeskal
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- Stefan-Meyer-Institute for Subatomic Physics, Austrian Academy of Science, 1030 Wien, Austria
| | - Catalina Curceanu
- Laboratori Nazionali di Frascati, INFN, 00044 Frascati, Italy
- IFIN-HH, Institutul National pentru Fizica si Inginerie Nucleara Horia Hulubei, 077125 Măgurele, Romania
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Qaswal AB, Ababneh O, Khreesha L, Al-Ani A, Suleihat A, Abbad M. Mathematical Modeling of Ion Quantum Tunneling Reveals Novel Properties of Voltage-Gated Channels and Quantum Aspects of Their Pathophysiology in Excitability-Related Disorders. PATHOPHYSIOLOGY 2021; 28:116-154. [PMID: 35366274 PMCID: PMC8830480 DOI: 10.3390/pathophysiology28010010] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 03/03/2021] [Accepted: 03/04/2021] [Indexed: 02/08/2023] Open
Abstract
Voltage-gated channels are crucial in action potential initiation and propagation and there are many diseases and disorders related to them. Additionally, the classical mechanics are the main mechanics used to describe the function of the voltage-gated channels and their related abnormalities. However, the quantum mechanics should be considered to unravel new aspects in the voltage-gated channels and resolve the problems and challenges that classical mechanics cannot solve. In the present study, the aim is to mathematically show that quantum mechanics can exhibit a powerful tendency to unveil novel electrical features in voltage-gated channels and be used as a promising tool to solve the problems and challenges in the pathophysiology of excitability-related diseases. The model of quantum tunneling of ions through the intracellular hydrophobic gate is used to evaluate the influence of membrane potential and gating free energy on the tunneling probability, single channel conductance, and quantum membrane conductance. This evaluation is mainly based on graphing the mathematical relationships between these variables. The obtained mathematical graphs showed that ions can achieve significant quantum membrane conductance, which can affect the resting membrane potential and the excitability of cells. In the present work, quantum mechanics reveals original electrical properties associated with voltage-gated channels and introduces new insights and implications into the pathophysiology of excitability- related disorders. In addition, the present work sets a mathematical and theoretical framework that can be utilized to conduct experimental studies in order to explore the quantum aspects of voltage-gated channels and the quantum bioelectrical property of biological membranes.
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Affiliation(s)
- Abdallah Barjas Qaswal
- Department of Internship Program, Jordan University Hospital, The University of Jordan, Amman 11942, Jordan
| | - Omar Ababneh
- Department of Anesthesia and Intensive Care, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Lubna Khreesha
- Department of Special Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Abdallah Al-Ani
- School of Medicine, The University of Jordan, Amman 11942, Jordan;
| | - Ahmad Suleihat
- Department of General Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan; (A.S.); (M.A.)
| | - Mutaz Abbad
- Department of General Surgery, School of Medicine, The University of Jordan, Amman 11942, Jordan; (A.S.); (M.A.)
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5
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Pedernales JS, Morley GW, Plenio MB. Motional Dynamical Decoupling for Interferometry with Macroscopic Particles. PHYSICAL REVIEW LETTERS 2020; 125:023602. [PMID: 32701327 DOI: 10.1103/physrevlett.125.023602] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Accepted: 05/29/2020] [Indexed: 06/11/2023]
Abstract
We extend the concept of dynamical decoupling from spin to mechanical degrees of freedom of macroscopic objects, for application in interferometry. In this manner, the superposition of matter waves can be made resilient to many important sources of noise when these are driven along suitable paths in space. As a concrete implementation, we present the case of levitated (or free falling) nanodiamonds hosting a color center in a magnetic field gradient. We point out that these interferometers are inherently affected by diamagnetic forces, which restrict the separation of the superposed states to distances that scale with the inverse of the magnetic field gradient. Periodic forcing of the mechanical degree of freedom is shown to overcome this limitation, achieving a linear-in-time growth of the separation distance independent of the magnetic field gradient, while simultaneously protecting the coherence of the superposition from environmental perturbations.
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Affiliation(s)
- Julen S Pedernales
- Institut für Theoretische Physik und IQST, Albert-Einstein-Allee 11, Universität Ulm, D-89081 Ulm, Germany
| | - Gavin W Morley
- Department of Physics, University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom
| | - Martin B Plenio
- Institut für Theoretische Physik und IQST, Albert-Einstein-Allee 11, Universität Ulm, D-89081 Ulm, Germany
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6
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Samanta AK, Amin M, Estillore AD, Roth N, Worbs L, Horke DA, Küpper J. Controlled beams of shock-frozen, isolated, biological and artificial nanoparticles. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2020; 7:024304. [PMID: 32341941 PMCID: PMC7166121 DOI: 10.1063/4.0000004] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Accepted: 04/01/2020] [Indexed: 05/05/2023]
Abstract
X-ray free-electron lasers promise diffractive imaging of single molecules and nanoparticles with atomic spatial resolution. This relies on the averaging of millions of diffraction patterns of identical particles, which should ideally be isolated in the gas phase and preserved in their native structure. Here, we demonstrated that polystyrene nanospheres and Cydia pomonella granulovirus can be transferred into the gas phase, isolated, and very quickly shock-frozen, i.e., cooled to 4 K within microseconds in a helium-buffer-gas cell, much faster than state-of-the-art approaches. Nanoparticle beams emerging from the cell were characterized using particle-localization microscopy with light-sheet illumination, which allowed for the full reconstruction of the particle beams, focused to < 100 μ m , as well as for the determination of particle flux and number density. The experimental results were quantitatively reproduced and rationalized through particle-trajectory simulations. We propose an optimized setup with cooling rates for particles of few-nanometers on nanosecond timescales. The produced beams of shock-frozen isolated nanoparticles provide a breakthrough in sample delivery, e.g., for diffractive imaging and microscopy or low-temperature nanoscience.
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Affiliation(s)
- Amit K. Samanta
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Muhamed Amin
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | - Armando D. Estillore
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany
| | | | | | | | - Jochen Küpper
- Author to whom correspondence should be addressed:. URL:https://www.controlled-molecule-imaging.org
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7
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Millen J, Monteiro TS, Pettit R, Vamivakas AN. Optomechanics with levitated particles. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2020; 83:026401. [PMID: 31825901 DOI: 10.1088/1361-6633/ab6100] [Citation(s) in RCA: 39] [Impact Index Per Article: 9.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Optomechanics is concerned with the use of light to control mechanical objects. As a field, it has been hugely successful in the production of precise and novel sensors, the development of low-dissipation nanomechanical devices, and the manipulation of quantum signals. Micro- and nano-particles levitated in optical fields act as nanoscale oscillators, making them excellent low-dissipation optomechanical objects, with minimal thermal contact to the environment when operating in vacuum. Levitated optomechanics is seen as the most promising route for studying high-mass quantum physics, with the promise of creating macroscopically separated superposition states at masses of 106 amu and above. Optical feedback, both using active monitoring or the passive interaction with an optical cavity, can be used to cool the centre-of-mass of levitated nanoparticles well below 1 mK, paving the way to operation in the quantum regime. In addition, trapped mesoscopic particles are the paradigmatic system for studying nanoscale stochastic processes, and have already demonstrated their utility in state-of-the-art force sensing.
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Affiliation(s)
- James Millen
- Department of Physics, King's College London, Strand, London, WC2R 2LS, United Kingdom
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8
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Pursehouse J, Murray AJ, Wätzel J, Berakdar J. Dynamic Double-Slit Experiment in a Single Atom. PHYSICAL REVIEW LETTERS 2019; 122:053204. [PMID: 30822012 DOI: 10.1103/physrevlett.122.053204] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2018] [Revised: 10/21/2018] [Indexed: 06/09/2023]
Abstract
A single-atom "double-slit" experiment is realized by photoionizing rubidium atoms using two independent low power lasers. The photoelectron wave of well-defined energy recedes to the continuum either from the 5P or 6P states in the same atom, resulting in two-path interference imaged in the far field using a photoelectron detector. Even though the lasers are independent and not phase locked, the transitions within the atom impart the phase relationship necessary for interference. The experiment is designed so that either 5P or 6P states are excited by one laser, before ionization by the second beam. The measurement cannot determine which excitation path is taken, resulting in interference in wave-vector space analogous to Young's double-slit studies. As the lasers are tunable in both frequency and intensity, the individual excitation-ionization pathways can be varied, allowing dynamic control of the interference term. Since the electron wave recedes in the Coulomb potential of the residual ion, a quantum model is used to capture the dynamics. Excellent agreement is found between theory and experiment.
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Affiliation(s)
- James Pursehouse
- Photon Science Institute, School of Physics & Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Andrew James Murray
- Photon Science Institute, School of Physics & Astronomy, University of Manchester, Manchester M13 9PL, United Kingdom
| | - Jonas Wätzel
- Martin-Luther-Universität Halle-Wittenberg, Institute of Physics, 06099 Halle/Saale, Germany
| | - Jamal Berakdar
- Martin-Luther-Universität Halle-Wittenberg, Institute of Physics, 06099 Halle/Saale, Germany
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9
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Yashiro W. Hard X-ray imaging microscopy with self-imaging phenomenon. Microscopy (Oxf) 2018; 67:303-316. [PMID: 30307556 DOI: 10.1093/jmicro/dfy040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Accepted: 09/11/2018] [Indexed: 11/12/2022] Open
Abstract
The self-imaging phenomenon referred to as the Talbot effect in the field of optics was discovered by H.F. Talbot in the 1830s, and is now widely used for imaging using not only visible light but also X-rays, electrons, neutrons, and matter waves. In this review, the author introduces the current progress being made in hard-X-ray imaging microscopy based on the self-imaging phenomenon. Hard-X-ray imaging microscopy is a promising technique for non-destructively visualizing internal structures in specimens with a spatial resolution up to a few tens of nanometers. The use of the self-imaging phenomenon makes it possible to realize highly sensitive phase-contrast X-ray imaging microscopes. These approaches have several advantages over conventional X-ray imaging microscopes, including the widely used Zernike X-ray phase-contrast microscopes, and can provide a powerful way of quantitative visualization with a high spatial resolution and a high sensitivity even for thick specimens.
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Affiliation(s)
- Wataru Yashiro
- Institute of Multidisciplinary Research for Advanced Materials (IMRAM), Tohoku University, Katahira 2-1-1, Aoba-ku, Sendai, Japan
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10
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Mairhofer L, Eibenberger S, Shayeghi A, Arndt M. A Quantum Ruler for Magnetic Deflectometry. ENTROPY 2018; 20:e20070516. [PMID: 33265606 PMCID: PMC7513036 DOI: 10.3390/e20070516] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 07/04/2018] [Accepted: 07/06/2018] [Indexed: 12/31/2022]
Abstract
Matter-wave near-field interference can imprint a nano-scale fringe pattern onto a molecular beam, which allows observing its shifts in the presence of even very small external forces. Here we demonstrate quantum interference of the pre-vitamin 7-dehydrocholesterol and discuss the conceptual challenges of magnetic deflectometry in a near-field interferometer as a tool to explore photochemical processes within molecules whose center of mass is quantum delocalized.
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Affiliation(s)
- Lukas Mairhofer
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Wien, Austria
| | - Sandra Eibenberger
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, D-14195 Berlin, Germany
| | - Armin Shayeghi
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Wien, Austria
| | - Markus Arndt
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Wien, Austria
- Correspondence: ; Tel.: +43-1-4277-51210
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12
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Dakić B, Radonjić M. Macroscopic Superpositions as Quantum Ground States. PHYSICAL REVIEW LETTERS 2017; 119:090401. [PMID: 28949556 DOI: 10.1103/physrevlett.119.090401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Indexed: 06/07/2023]
Abstract
We study the question of what kind of a macroscopic superposition can(not) naturally exist as a ground state of some gapped local many-body Hamiltonian. We derive an upper bound on the energy gap of an arbitrary physical Hamiltonian provided that its ground state is a superposition of two well-distinguishable macroscopic "semiclassical" states. For a large class of macroscopic superposition states we show that the gap vanishes in the macroscopic limit. This in turn shows that preparation of such states by simple cooling to the ground state is not experimentally feasible and requires a different strategy. Our approach is very general and can be used to rule out a variety of quantum states, some of which do not even exhibit macroscopic quantum properties. Moreover, our methods and results can be used for addressing quantum marginal related problems.
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Affiliation(s)
- Borivoje Dakić
- Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences, Boltzmanngasse 3, A-1090 Vienna, Austria
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Milan Radonjić
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
- Institute of Physics Belgrade, University of Belgrade, Pregrevica 118, 11080 Belgrade, Serbia
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13
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Mairhofer L, Eibenberger S, Cotter JP, Romirer M, Shayeghi A, Arndt M. Quantum-Assisted Metrology of Neutral Vitamins in the Gas Phase. Angew Chem Int Ed Engl 2017; 56:10947-10951. [PMID: 28599088 PMCID: PMC5582605 DOI: 10.1002/anie.201704916] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2017] [Indexed: 11/11/2022]
Abstract
It has recently been shown that matter-wave interferometry can be used to imprint a periodic nanostructure onto a molecular beam, which provides a highly sensitive tool for beam displacement measurements. Herein, we used this feature to measure electronic properties of provitamin A, vitamin E, and vitamin K1 in the gas phase for the first time. The shift of the matter-wave fringes in a static electric field encodes the molecular susceptibility and the time-averaged dynamic electric dipole moment. The dependence of the fringe pattern on the intensity of the central light-wave diffraction grating was used to determine the molecular optical polarizability. Comparison of our experimental findings with molecular dynamics simulations and density functional theory provides a rich picture of the electronic structures and dynamics of these biomolecules in the gas phase with β-carotene as a particularly interesting example.
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Affiliation(s)
- Lukas Mairhofer
- Faculty of Physics, VCQUniversity of ViennaBoltzmanngasse 51090ViennaAustria
| | - Sandra Eibenberger
- Faculty of Physics, VCQUniversity of ViennaBoltzmanngasse 51090ViennaAustria
- Lyman LaboratoryHarvard UniversityDepartment of Physics17 Oxford StreetCambridgeMA02138USA
| | - Joseph P. Cotter
- Faculty of Physics, VCQUniversity of ViennaBoltzmanngasse 51090ViennaAustria
- Centre for cold matterBlackett LaboratoryImperial CollegePrince Consort RoadLondonSW7 2BWUK
| | - Marion Romirer
- Faculty of Physics, VCQUniversity of ViennaBoltzmanngasse 51090ViennaAustria
| | - Armin Shayeghi
- Faculty of Physics, VCQUniversity of ViennaBoltzmanngasse 51090ViennaAustria
| | - Markus Arndt
- Faculty of Physics, VCQUniversity of ViennaBoltzmanngasse 51090ViennaAustria
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14
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Mairhofer L, Eibenberger S, Cotter JP, Romirer M, Shayeghi A, Arndt M. Quanteninterferenzexperimente für die Vermessung von Vitaminen in der Gasphase. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201704916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Lukas Mairhofer
- Fakultät für Physik, VCQ; Universität Wien; Boltzmanngasse 5 1090 Wien Österreich
| | - Sandra Eibenberger
- Fakultät für Physik, VCQ; Universität Wien; Boltzmanngasse 5 1090 Wien Österreich
- Lyman Laboratory; Harvard University; Department of Physics; 17 Oxford Street Cambridge MA 02138 USA
| | - Joseph P. Cotter
- Fakultät für Physik, VCQ; Universität Wien; Boltzmanngasse 5 1090 Wien Österreich
- Centre for cold matter; Blackett Laboratory; Imperial College; Prince Consort Road London SW7 2BW Großbritannien
| | - Marion Romirer
- Fakultät für Physik, VCQ; Universität Wien; Boltzmanngasse 5 1090 Wien Österreich
| | - Armin Shayeghi
- Fakultät für Physik, VCQ; Universität Wien; Boltzmanngasse 5 1090 Wien Österreich
| | - Markus Arndt
- Fakultät für Physik, VCQ; Universität Wien; Boltzmanngasse 5 1090 Wien Österreich
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15
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Schätti J, Sezer U, Pedalino S, Cotter JP, Arndt M, Mayor M, Köhler V. Tailoring the volatility and stability of oligopeptides. JOURNAL OF MASS SPECTROMETRY : JMS 2017; 52:550-556. [PMID: 28608445 PMCID: PMC5601229 DOI: 10.1002/jms.3959] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/23/2017] [Revised: 06/08/2017] [Accepted: 06/08/2017] [Indexed: 06/07/2023]
Abstract
Amino acids are essential building blocks of life, and fluorinated derivatives have gained interest in chemistry and medicine. Modern mass spectrometry has enabled the study of oligo- and polypeptides as isolated entities in the gas phase, but predominantly as singly or even multiply charged species. While laser desorption of neutral peptides into adiabatically expanding supersonic noble gas jets is possible, UV-VIS spectroscopy, electric or magnetic deflectometry as well as quantum interferometry would profit from the possibility to prepare thermally slow molecular beams. This has typically been precluded by the fragility of the peptide bond and the fact that a peptide would rather 'fry', i.e. denature and fragment than 'fly'. Here, we explore how tailored perfluoroalkyl functionalization can reduce the intermolecular binding and thus increase the volatility of peptides and compare it to previously explored methylation, acylation and amidation of peptides. We show that this strategy is essential and enables the formation of thermal beams of intact neutral tripeptides, whereas only fragments were observed for an extensively fluoroalkyl-decorated nonapeptide. © 2017 The Authors. Journal of Mass Spectrometry Published by John Wiley & Sons Ltd.
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Affiliation(s)
- J. Schätti
- University of BaselDepartment of ChemistryBasel4056Switzerland
| | - U. Sezer
- University of ViennaFaculty of PhysicsBoltzmanngasse 51090ViennaAustria
| | - S. Pedalino
- University of ViennaFaculty of PhysicsBoltzmanngasse 51090ViennaAustria
| | - J. P. Cotter
- University of ViennaFaculty of PhysicsBoltzmanngasse 51090ViennaAustria
| | - M. Arndt
- University of ViennaFaculty of PhysicsBoltzmanngasse 51090ViennaAustria
| | - M. Mayor
- University of BaselDepartment of ChemistryBasel4056Switzerland
- Karlsruhe Institute of TechnologyInstitute for NanotechnologyHermann‐von‐Helmholtz‐Platz 176344Eggenstein‐LeopoldshafenGermany
| | - V. Köhler
- University of BaselDepartment of ChemistryBasel4056Switzerland
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16
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Cotter JP, Brand C, Knobloch C, Lilach Y, Cheshnovsky O, Arndt M. In search of multipath interference using large molecules. SCIENCE ADVANCES 2017; 3:e1602478. [PMID: 28819641 PMCID: PMC5553822 DOI: 10.1126/sciadv.1602478] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/12/2016] [Accepted: 07/06/2017] [Indexed: 06/07/2023]
Abstract
The superposition principle is fundamental to the quantum description of both light and matter. Recently, a number of experiments have sought to directly test this principle using coherent light, single photons, and nuclear spin states. We extend these experiments to massive particles for the first time. We compare the interference patterns arising from a beam of large dye molecules diffracting at single, double, and triple slit material masks to place limits on any high-order, or multipath, contributions. We observe an upper bound of less than one particle in a hundred deviating from the expectations of quantum mechanics over a broad range of transverse momenta and de Broglie wavelength.
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Affiliation(s)
- Joseph P. Cotter
- Faculty of Physics, Vienna Center for Quantum Science and Technology, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Christian Brand
- Faculty of Physics, Vienna Center for Quantum Science and Technology, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Christian Knobloch
- Faculty of Physics, Vienna Center for Quantum Science and Technology, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Yigal Lilach
- Center for Nanoscience and Nanotechnology, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Ori Cheshnovsky
- Center for Nanoscience and Nanotechnology, Tel Aviv University, 69978 Tel Aviv, Israel
- School of Chemistry, Raymond and Beverly Faculty of Exact Sciences, Tel Aviv University, 69978 Tel Aviv, Israel
| | - Markus Arndt
- Faculty of Physics, Vienna Center for Quantum Science and Technology, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
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17
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Sezer U, Geyer P, Kriegleder M, Debiossac M, Shayeghi A, Arndt M, Felix L, Mayor M. Selective photodissociation of tailored molecular tags as a tool for quantum optics. BEILSTEIN JOURNAL OF NANOTECHNOLOGY 2017; 8:325-333. [PMID: 28243571 PMCID: PMC5301912 DOI: 10.3762/bjnano.8.35] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 01/17/2017] [Indexed: 06/06/2023]
Abstract
Recent progress in synthetic chemistry and molecular quantum optics has enabled demonstrations of the quantum mechanical wave-particle duality for complex particles, with masses exceeding 10 kDa. Future experiments with even larger objects will require new optical preparation and manipulation methods that shall profit from the possibility to cleave a well-defined molecular tag from a larger parent molecule. Here we present the design and synthesis of two model compounds as well as evidence for the photoinduced beam depletion in high vacuum in one case.
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Affiliation(s)
- Ugur Sezer
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Philipp Geyer
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Moritz Kriegleder
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Maxime Debiossac
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Armin Shayeghi
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Markus Arndt
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Lukas Felix
- Department of Chemistry, University of Basel, St. Johannsring 19, CH-4056 Basel, Switzerland
| | - Marcel Mayor
- Department of Chemistry, University of Basel, St. Johannsring 19, CH-4056 Basel, Switzerland
- Institute of Nanotechnology (INT), Karlsruhe Institute of Technology (KIT), Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany
- Lehn Institute of Functional Materials (LIFM), Sun Yat-Sen University (SYSU), Xingang Rd. W., Guangzhou, China
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18
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Salari V, Naeij H, Shafiee A. Quantum Interference and Selectivity through Biological Ion Channels. Sci Rep 2017; 7:41625. [PMID: 28134331 PMCID: PMC5278555 DOI: 10.1038/srep41625] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Accepted: 12/06/2016] [Indexed: 11/24/2022] Open
Abstract
The mechanism of selectivity in ion channels is still an open question in biology for more than half a century. Here, we suggest that quantum interference can be a solution to explain the selectivity mechanism in ion channels since interference happens between similar ions through the same size of ion channels. In this paper, we simulate two neighboring ion channels on a cell membrane with the famous double-slit experiment in physics to investigate whether there is any possibility of matter-wave interference of ions via movement through ion channels. Our obtained decoherence timescales indicate that the quantum states of ions can only survive for short times, i.e. ≈100 picoseconds in each channel and ≈17-53 picoseconds outside the channels, giving the result that the quantum interference of ions seems unlikely due to environmental decoherence. However, we discuss our results and raise few points, which increase the possibility of interference.
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Affiliation(s)
- Vahid Salari
- Department of Physics, Isfahan University of Technology, Isfahan 84156-83111, Iran
- School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran, Iran
| | - Hamidreza Naeij
- Research Group on Foundations of Quantum Theory and Information, Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran, Iran
| | - Afshin Shafiee
- School of Physics, Institute for Research in Fundamental Sciences (IPM), P.O. Box 19395-5531, Tehran, Iran
- Research Group on Foundations of Quantum Theory and Information, Department of Chemistry, Sharif University of Technology, P.O. Box 11365-9516, Tehran, Iran
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19
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Rodewald J, Haslinger P, Dörre N, Stickler BA, Shayeghi A, Hornberger K, Arndt M. New avenues for matter-wave-enhanced spectroscopy. APPLIED PHYSICS. B, LASERS AND OPTICS 2016; 123:3. [PMID: 28018052 PMCID: PMC5148790 DOI: 10.1007/s00340-016-6573-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/29/2016] [Accepted: 11/04/2016] [Indexed: 06/06/2023]
Abstract
We present matter-wave interferometry as a tool to advance spectroscopy for a wide class of nanoparticles, clusters and molecules. The high sensitivity of de Broglie interference fringes to external perturbations enables measurements in the limit of an individual particle absorbing only a single photon on average, or even no photon at all. The method allows one to extract structural and electronic information from the loss of the interference contrast. It is minimally invasive and works even for dilute ensembles.
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Affiliation(s)
- Jonas Rodewald
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Philipp Haslinger
- University of California, Berkeley, Leconte/Birge Hall, Berkeley, CA 94720 USA
| | - Nadine Dörre
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Benjamin A. Stickler
- Faculty of Physics, University of Duisburg-Essen, Lotharstraße 1-21, Duisburg, Germany
| | - Armin Shayeghi
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Klaus Hornberger
- Faculty of Physics, University of Duisburg-Essen, Lotharstraße 1-21, Duisburg, Germany
| | - Markus Arndt
- Faculty of Physics, VCQ, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria
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20
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Kincaid J, McLelland K. Measurement-induced decoherence and information in double-slit interference. AMERICAN JOURNAL OF PHYSICS 2016; 84:522-530. [PMID: 27807373 PMCID: PMC5087820 DOI: 10.1119/1.4943585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The double slit experiment provides a classic example of both interference and the effect of observation in quantum physics. When particles are sent individually through a pair of slits, a wave-like interference pattern develops, but no such interference is found when one observes which "path" the particles take. We present a model of interference, dephasing, and measurement-induced decoherence in a one-dimensional version of the double-slit experiment. Using this model, we demonstrate how the loss of interference in the system is correlated with the information gain by the measuring apparatus/observer. In doing so, we give a modern account of measurement in this paradigmatic example of quantum physics that is accessible to students taking quantum mechanics at the graduate or senior undergraduate levels.
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21
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Vallone G, Dequal D, Tomasin M, Vedovato F, Schiavon M, Luceri V, Bianco G, Villoresi P. Interference at the Single Photon Level Along Satellite-Ground Channels. PHYSICAL REVIEW LETTERS 2016; 116:253601. [PMID: 27391721 DOI: 10.1103/physrevlett.116.253601] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2016] [Indexed: 06/06/2023]
Abstract
Quantum interference arising from the superposition of states is striking evidence of the validity of quantum mechanics, confirmed in many experiments and also exploited in applications. However, as for any scientific theory, quantum mechanics is valid within the limits in which it has been experimentally verified. In order to extend such limits, it is necessary to observe quantum interference in unexplored conditions such as moving terminals at large distances in space. Here, we experimentally demonstrate single photon interference at a ground station due to the coherent superposition of two temporal modes reflected by a rapidly moving satellite a thousand kilometers away. The relative speed of the satellite induces a varying modulation in the interference pattern. The measurement of the satellite distance in real time by laser ranging allows us to precisely predict the instantaneous value of the interference phase. We then observed the interference patterns with a visibility up to 67% with three different satellites and with a path length up to 5000 km. Our results attest to the viability of photon temporal modes for fundamental tests of physics and quantum communication in space.
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Affiliation(s)
- Giuseppe Vallone
- Dipartimento di Ingegneria dell'Informazione, Università degli Studi di Padova, Padova 35131, Italy
| | - Daniele Dequal
- Dipartimento di Ingegneria dell'Informazione, Università degli Studi di Padova, Padova 35131, Italy
| | - Marco Tomasin
- Dipartimento di Ingegneria dell'Informazione, Università degli Studi di Padova, Padova 35131, Italy
| | - Francesco Vedovato
- Dipartimento di Ingegneria dell'Informazione, Università degli Studi di Padova, Padova 35131, Italy
| | - Matteo Schiavon
- Dipartimento di Ingegneria dell'Informazione, Università degli Studi di Padova, Padova 35131, Italy
| | | | - Giuseppe Bianco
- Matera Laser Ranging Observatory, Agenzia Spaziale Italiana, Matera 75100, Italy
| | - Paolo Villoresi
- Dipartimento di Ingegneria dell'Informazione, Università degli Studi di Padova, Padova 35131, Italy
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22
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Mari A, De Palma G, Giovannetti V. Experiments testing macroscopic quantum superpositions must be slow. Sci Rep 2016; 6:22777. [PMID: 26959656 PMCID: PMC4784303 DOI: 10.1038/srep22777] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2015] [Accepted: 02/23/2016] [Indexed: 11/09/2022] Open
Abstract
We consider a thought experiment where the preparation of a macroscopically massive or charged particle in a quantum superposition and the associated dynamics of a distant test particle apparently allow for superluminal communication. We give a solution to the paradox which is based on the following fundamental principle: any local experiment, discriminating a coherent superposition from an incoherent statistical mixture, necessarily requires a minimum time proportional to the mass (or charge) of the system. For a charged particle, we consider two examples of such experiments, and show that they are both consistent with the previous limitation. In the first, the measurement requires to accelerate the charge, that can entangle with the emitted photons. In the second, the limitation can be ascribed to the quantum vacuum fluctuations of the electromagnetic field. On the other hand, when applied to massive particles our result provides an indirect evidence for the existence of gravitational vacuum fluctuations and for the possibility of entangling a particle with quantum gravitational radiation.
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Affiliation(s)
- Andrea Mari
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, I-56126 Pisa, Italy
| | - Giacomo De Palma
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, I-56126 Pisa, Italy.,INFN, Edificio C, Largo Bruno Pontecorvo, 3, 56127 Pisa PI, Italy
| | - Vittorio Giovannetti
- NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, I-56126 Pisa, Italy
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23
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Vinante A, Bahrami M, Bassi A, Usenko O, Wijts G, Oosterkamp TH. Upper Bounds on Spontaneous Wave-Function Collapse Models Using Millikelvin-Cooled Nanocantilevers. PHYSICAL REVIEW LETTERS 2016; 116:090402. [PMID: 26991158 DOI: 10.1103/physrevlett.116.090402] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Indexed: 06/05/2023]
Abstract
Collapse models predict a tiny violation of energy conservation, as a consequence of the spontaneous collapse of the wave function. This property allows us to set experimental bounds on their parameters. We consider an ultrasoft magnetically tipped nanocantilever cooled to millikelvin temperature. The thermal noise of the cantilever fundamental mode has been accurately estimated in the range 0.03-1 K, and any other excess noise is found to be negligible within the experimental uncertainty. From the measured data and the cantilever geometry, we estimate the upper bound on the continuous spontaneous localization collapse rate in a wide range of the correlation length r_{C}. Our upper bound improves significantly previous constraints for r_{C}>10^{-6} m, and partially excludes the enhanced collapse rate suggested by Adler. We discuss future improvements.
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Affiliation(s)
- A Vinante
- Istituto Nazionale di Fisica Nucleare (INFN), TIFPA, I-38123 Povo, Trento, Italy
- Istituto di Fotonica e Nanotecnologie, CNR-Fondazione Bruno Kessler, I-38123 Povo, Trento, Italy
| | - M Bahrami
- Department of Physics, University of Trieste, Strada Costiera 11, 34014 Trieste, Italy
- Istituto Nazionale di Fisica Nucleare (INFN), Trieste Section, Via Valerio 2, 34127 Trieste, Italy
| | - A Bassi
- Department of Physics, University of Trieste, Strada Costiera 11, 34014 Trieste, Italy
- Istituto Nazionale di Fisica Nucleare (INFN), Trieste Section, Via Valerio 2, 34127 Trieste, Italy
| | - O Usenko
- Leiden Institute of Physics, Leiden University, Post Office Box 9504, 2300 RA Leiden, The Netherlands
| | - G Wijts
- Leiden Institute of Physics, Leiden University, Post Office Box 9504, 2300 RA Leiden, The Netherlands
| | - T H Oosterkamp
- Leiden Institute of Physics, Leiden University, Post Office Box 9504, 2300 RA Leiden, The Netherlands
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24
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Quantum superposition at the half-metre scale. Nature 2016; 528:530-3. [PMID: 26701053 DOI: 10.1038/nature16155] [Citation(s) in RCA: 223] [Impact Index Per Article: 27.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2015] [Accepted: 10/09/2015] [Indexed: 11/08/2022]
Abstract
The quantum superposition principle allows massive particles to be delocalized over distant positions. Though quantum mechanics has proved adept at describing the microscopic world, quantum superposition runs counter to intuitive conceptions of reality and locality when extended to the macroscopic scale, as exemplified by the thought experiment of Schrödinger's cat. Matter-wave interferometers, which split and recombine wave packets in order to observe interference, provide a way to probe the superposition principle on macroscopic scales and explore the transition to classical physics. In such experiments, large wave-packet separation is impeded by the need for long interaction times and large momentum beam splitters, which cause susceptibility to dephasing and decoherence. Here we use light-pulse atom interferometry to realize quantum interference with wave packets separated by up to 54 centimetres on a timescale of 1 second. These results push quantum superposition into a new macroscopic regime, demonstrating that quantum superposition remains possible at the distances and timescales of everyday life. The sub-nanokelvin temperatures of the atoms and a compensation of transverse optical forces enable a large separation while maintaining an interference contrast of 28 per cent. In addition to testing the superposition principle in a new regime, large quantum superposition states are vital to exploring gravity with atom interferometers in greater detail. We anticipate that these states could be used to increase sensitivity in tests of the equivalence principle, measure the gravitational Aharonov-Bohm effect, and eventually detect gravitational waves and phase shifts associated with general relativity.
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25
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Pizzi R, Wang R, Rossetti D. Human Visual System as a Double-Slit Single Photon Interference Sensor: A Comparison between Modellistic and Biophysical Tests. PLoS One 2016; 11:e0147464. [PMID: 26816029 PMCID: PMC4729532 DOI: 10.1371/journal.pone.0147464] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Accepted: 01/03/2016] [Indexed: 11/19/2022] Open
Abstract
This paper describes a computational approach to the theoretical problems involved in the Young's single-photon double-slit experiment, focusing on a simulation of this experiment in the absence of measuring devices. Specifically, the human visual system is used in place of a photomultiplier or similar apparatus. Beginning with the assumption that the human eye perceives light in the presence of very few photons, we measure human eye performance as a sensor in a double-slit one-photon-at-a-time experimental setup. To interpret the results, we implement a simulation algorithm and compare its results with those of human subjects under identical experimental conditions. In order to evaluate the perceptive parameters exactly, which vary depending on the light conditions and on the subject's sensitivity, we first review the existing literature on the biophysics of the human eye in the presence of a dim light source, and then use the known values of the experimental variables to set the parameters of the computational simulation. The results of the simulation and their comparison with the experiment involving human subjects are reported and discussed. It is found that, while the computer simulation indicates that the human eye has the capacity to detect the corpuscular nature of photons under these conditions, this was not observed in practice. The possible reasons for the difference between theoretical prediction and experimental results are discussed.
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Affiliation(s)
- Rita Pizzi
- Department of Computer Science, University of Milan, Milan, Italy
| | - Rui Wang
- Department of Computer Science, University of Milan, Milan, Italy
| | - Danilo Rossetti
- Department of Computer Science, University of Milan, Milan, Italy
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26
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Jambrina PG, Aldegunde J, Aoiz FJ, Sneha M, Zare RN. Effects of reagent rotation on interferences in the product angular distributions of chemical reactions. Chem Sci 2016; 7:642-649. [PMID: 28791109 PMCID: PMC5523120 DOI: 10.1039/c5sc03373j] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2015] [Accepted: 10/02/2015] [Indexed: 12/26/2022] Open
Abstract
Differential cross sections (DSCs) of the HD(v', j') product for the reaction of H atoms with supersonically cooled D2 molecules in a small number of initial rotational states have been measured at a collision energy of 1.97 eV. These DCSs show an oscillatory pattern that results from interferences caused by different dynamical scattering mechanisms leading to products scattered into the same solid angle. The interferences depend on the initial rotational state j of the D2(v = 0, j) reagent and diminish in strength with increasing rotation. We present here a detailed explanation for this behavior and how each dynamical scattering mechanism has a dependence on the helicity Ω, the projection of the initial rotational angular momentum j of the D2 reagent on the approach direction. Each helicity corresponds to a different internuclear axis distribution, with the consequence that the dependence on Ω reveals the preference of the different quasiclassical mechanisms as a function of approach direction. We believe that these results are general and will appear in any reaction for which several mechanisms are operative.
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Affiliation(s)
- P G Jambrina
- Departamento de Química Física I , Facultad de Química , Universidad Complutense de Madrid , 28040 , Spain .
| | - J Aldegunde
- Departamento de Química Física , Universidad de Salamanca , Salamanca , Spain
| | - F J Aoiz
- Departamento de Química Física I , Facultad de Química , Universidad Complutense de Madrid , 28040 , Spain .
| | - M Sneha
- Department of Chemistry , Stanford University , Stanford , California 94305-5080 , USA .
| | - R N Zare
- Department of Chemistry , Stanford University , Stanford , California 94305-5080 , USA .
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27
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Treutlein P. Matter-wave interference: Nanomechanical answer to Einstein. NATURE NANOTECHNOLOGY 2015; 10:832-833. [PMID: 26440720 DOI: 10.1038/nnano.2015.241] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Affiliation(s)
- Philipp Treutlein
- Department of Physics, University of Basel, Klingelbergstrasse 82, 4056 Basel, Switzerland
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28
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Simulated Interactive Research Experiments as Educational Tools for Advanced Science. Sci Rep 2015; 5:14108. [PMID: 26370627 PMCID: PMC4572923 DOI: 10.1038/srep14108] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2015] [Accepted: 08/17/2015] [Indexed: 11/08/2022] Open
Abstract
Experimental research has become complex and thus a challenge to science education. Only very few students can typically be trained on advanced scientific equipment. It is therefore important to find new tools that allow all students to acquire laboratory skills individually and independent of where they are located. In a design-based research process we have investigated the feasibility of using a virtual laboratory as a photo-realistic and scientifically valid representation of advanced scientific infrastructure to teach modern experimental science, here, molecular quantum optics. We found a concept based on three educational principles that allows undergraduate students to become acquainted with procedures and concepts of a modern research field. We find a significant increase in student understanding using our Simulated Interactive Research Experiment (SiReX), by evaluating the learning outcomes with semi-structured interviews in a pre/post design. This suggests that this concept of an educational tool can be generalized to disseminate findings in other fields.
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29
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Lombardo D, Twamley J. Deterministic Creation of Macroscopic Cat States. Sci Rep 2015; 5:13884. [PMID: 26345157 PMCID: PMC4561959 DOI: 10.1038/srep13884] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2015] [Accepted: 07/28/2015] [Indexed: 11/13/2022] Open
Abstract
Despite current technological advances, observing quantum mechanical effects outside of the nanoscopic realm is extremely challenging. For this reason, the observation of such effects on larger scale systems is currently one of the most attractive goals in quantum science. Many experimental protocols have been proposed for both the creation and observation of quantum states on macroscopic scales, in particular, in the field of optomechanics. The majority of these proposals, however, rely on performing measurements, making them probabilistic. In this work we develop a completely deterministic method of macroscopic quantum state creation. We study the prototypical optomechanical Membrane In The Middle model and show that by controlling the membrane’s opacity, and through careful choice of the optical cavity initial state, we can deterministically create and grow the spatial extent of the membrane’s position into a large cat state. It is found that by using a Bose-Einstein condensate as a membrane high fidelity cat states with spatial separations of up to ∼300 nm can be achieved.
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Affiliation(s)
- Daniel Lombardo
- Centre for Engineered Quantum Systems, Department of Physics and Astronomy, Macquarie University, Sydney, NSW 2109, Australia
| | - Jason Twamley
- Centre for Engineered Quantum Systems, Department of Physics and Astronomy, Macquarie University, Sydney, NSW 2109, Australia
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30
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Correlated random walks caused by dynamical wavefunction collapse. Sci Rep 2015; 5:13380. [PMID: 26303388 PMCID: PMC4548188 DOI: 10.1038/srep13380] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2015] [Accepted: 07/24/2015] [Indexed: 11/11/2022] Open
Abstract
Wavefunction collapse models modify Schrödinger’s equation so that it describes the collapse of a superposition of macroscopically distinguishable states as a dynamical process. This provides a basis for the resolution of the quantum measurement problem. An additional generic consequence of the collapse mechanism is that it causes particles to exhibit a tiny random diffusive motion. Here it is shown that for the continuous spontaneous localization (CSL) model—one of the most well developed collapse models—the diffusions of two sufficiently nearby particles are positively correlated. An experimental test of this effect is proposed in which random displacements of pairs of free nanoparticles are measured after they have been simultaneously released from nearby traps. The experiment must be carried out at sufficiently low temperature and pressure in order for the collapse effects to dominate over the ambient environmental noise. It is argued that these constraints can be satisfied by current technologies for a large region of the viable parameter space of the CSL model. The effect disappears as the separation between particles exceeds the CSL length scale. The test therefore provides a means of bounding this length scale.
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31
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Kuhn S, Asenbaum P, Kosloff A, Sclafani M, Stickler BA, Nimmrichter S, Hornberger K, Cheshnovsky O, Patolsky F, Arndt M. Cavity-Assisted Manipulation of Freely Rotating Silicon Nanorods in High Vacuum. NANO LETTERS 2015; 15:5604-8. [PMID: 26167662 PMCID: PMC4538454 DOI: 10.1021/acs.nanolett.5b02302] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Optical control of nanoscale objects has recently developed into a thriving field of research with far-reaching promises for precision measurements, fundamental quantum physics and studies on single-particle thermodynamics. Here, we demonstrate the optical manipulation of silicon nanorods in high vacuum. Initially, we sculpture these particles into a silicon substrate with a tailored geometry to facilitate their launch into high vacuum by laser-induced mechanical cleavage. We manipulate and trace their center-of-mass and rotational motion through the interaction with an intense intracavity field. Our experiments show that the anisotropy of the nanorotors leads to optical forces that are three times stronger than on silicon nanospheres of the same mass. The optical torque experienced by the spinning rods will enable cooling of the rotational motion and torsional optomechanics in a dissipation-free environment.
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Affiliation(s)
- Stefan Kuhn
- University
of Vienna, Faculty of Physics, VCQ, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Peter Asenbaum
- University
of Vienna, Faculty of Physics, VCQ, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Alon Kosloff
- School
of Chemistry, Tel-Aviv University, Ramat-Aviv 69978, Israel
| | - Michele Sclafani
- University
of Vienna, Faculty of Physics, VCQ, Boltzmanngasse 5, 1090 Vienna, Austria
| | | | | | - Klaus Hornberger
- University
of Duisburg-Essen, Lotharstraße
1, 47048 Duisburg, Germany
| | - Ori Cheshnovsky
- School
of Chemistry, Tel-Aviv University, Ramat-Aviv 69978, Israel
| | | | - Markus Arndt
- University
of Vienna, Faculty of Physics, VCQ, Boltzmanngasse 5, 1090 Vienna, Austria
- E-mail:
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32
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How gravity kills Schrödinger's cat. Nature 2015. [DOI: 10.1038/nature.2015.17773] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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33
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Coherence in the presence of absorption and heating in a molecule interferometer. Nat Commun 2015; 6:7336. [PMID: 26066053 PMCID: PMC4477035 DOI: 10.1038/ncomms8336] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Accepted: 04/28/2015] [Indexed: 11/08/2022] Open
Abstract
Matter-wave interferometry can be used to probe the foundations of physics and to enable precise measurements of particle properties and fundamental constants. It relies on beam splitters that coherently divide the wave function. In atom interferometers, such elements are often realised using lasers by exploiting the dipole interaction or through photon absorption. It is intriguing to extend these ideas to complex molecules where the energy of an absorbed photon can rapidly be redistributed across many internal degrees of freedom. Here, we provide evidence that center-of-mass coherence can be maintained even when the internal energy and entropy of the interfering particle are substantially increased by absorption of photons from a standing light wave. Each photon correlates the molecular center-of-mass wave function with its internal temperature and splits it into a superposition with opposite momenta in addition to the beam-splitting action of the optical dipole potential.
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34
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35
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Sezer U, Wörner L, Horak J, Felix L, Tüxen J, Götz C, Vaziri A, Mayor M, Arndt M. Laser-induced acoustic desorption of natural and functionalized biochromophores. Anal Chem 2015; 87:5614-9. [PMID: 25946522 PMCID: PMC4455108 DOI: 10.1021/acs.analchem.5b00601] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
Laser-induced acoustic desorption
(LIAD) has recently been established
as a tool for analytical chemistry. It is capable of launching intact,
neutral, or low charged molecules into a high vacuum environment.
This makes it ideally suited to mass spectrometry. LIAD can be used
with fragile biomolecules and very massive compounds alike. Here,
we apply LIAD time-of-flight mass spectrometry (TOF-MS) to the natural
biochromophores chlorophyll, hemin, bilirubin, and biliverdin and
to high mass fluoroalkyl-functionalized porphyrins. We characterize
the variation in the molecular fragmentation patterns as a function
of the desorption and the VUV postionization laser intensity. We find
that LIAD can produce molecular beams an order of magnitude slower
than matrix-assisted laser desorption (MALD), although this depends
on the substrate material. Using titanium foils we observe a most
probable velocity of 20 m/s for functionalized molecules with a mass m = 10 000 Da.
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Affiliation(s)
- Uğur Sezer
- †University of Vienna, Faculty of Physics, VCQ and QuNaBioS, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Lisa Wörner
- †University of Vienna, Faculty of Physics, VCQ and QuNaBioS, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Johannes Horak
- †University of Vienna, Faculty of Physics, VCQ and QuNaBioS, Boltzmanngasse 5, 1090 Vienna, Austria
| | - Lukas Felix
- ‡University of Basel, Department of Chemistry, St. Johannsring 19, 4056 Basel, Switzerland
| | - Jens Tüxen
- ‡University of Basel, Department of Chemistry, St. Johannsring 19, 4056 Basel, Switzerland
| | - Christoph Götz
- §University of Vienna, Max F. Perutz Laboratories, Research Institute of Molecular Pathology, QuNaBioS, Doktor-Bohr-Gasse 7, 1030 Vienna, Austria
| | - Alipasha Vaziri
- §University of Vienna, Max F. Perutz Laboratories, Research Institute of Molecular Pathology, QuNaBioS, Doktor-Bohr-Gasse 7, 1030 Vienna, Austria
| | - Marcel Mayor
- ‡University of Basel, Department of Chemistry, St. Johannsring 19, 4056 Basel, Switzerland.,∥Karlsruhe Institute of Technology (KIT), Institute of Nanotechnology, P.O. Box 3640, 76021 Karlsruhe, Germany
| | - Markus Arndt
- †University of Vienna, Faculty of Physics, VCQ and QuNaBioS, Boltzmanngasse 5, 1090 Vienna, Austria
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36
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Bateman J, McHardy I, Merle A, Morris TR, Ulbricht H. On the existence of low-mass dark matter and its direct detection. Sci Rep 2015; 5:8058. [PMID: 25622565 PMCID: PMC4306971 DOI: 10.1038/srep08058] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Accepted: 12/17/2014] [Indexed: 11/21/2022] Open
Abstract
Dark Matter (DM) is an elusive form of matter which has been postulated to explain astronomical observations through its gravitational effects on stars and galaxies, gravitational lensing of light around these, and through its imprint on the Cosmic Microwave Background (CMB). This indirect evidence implies that DM accounts for as much as 84.5% of all matter in our Universe, yet it has so far evaded all attempts at direct detection, leaving such confirmation and the consequent discovery of its nature as one of the biggest challenges in modern physics. Here we present a novel form of low-mass DM χ that would have been missed by all experiments so far. While its large interaction strength might at first seem unlikely, neither constraints from particle physics nor cosmological/astronomical observations are sufficient to rule out this type of DM, and it motivates our proposal for direct detection by optomechanics technology which should soon be within reach, namely, through the precise position measurement of a levitated mesoscopic particle which will be perturbed by elastic collisions with χ particles. We show that a recently proposed nanoparticle matter-wave interferometer, originally conceived for tests of the quantum superposition principle, is sensitive to these collisions, too.
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Affiliation(s)
- James Bateman
- Quantum, Light and Matter, Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Ian McHardy
- Astronomy, Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Alexander Merle
- 1] High Energy Physics Theory, Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, United Kingdom [2] Max-Planck-Institut für Physik (Werner-Heisenberg-Institut), Föhringer Ring 6, 80805 München, Germany
| | - Tim R Morris
- High Energy Physics Theory, Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, United Kingdom
| | - Hendrik Ulbricht
- Quantum, Light and Matter, Physics and Astronomy, University of Southampton, Southampton SO17 1BJ, United Kingdom
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37
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Bera S, Motwani B, Singh TP, Ulbricht H. A proposal for the experimental detection of CSL induced random walk. Sci Rep 2015; 5:7664. [PMID: 25563619 PMCID: PMC4288224 DOI: 10.1038/srep07664] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2014] [Accepted: 12/03/2014] [Indexed: 11/13/2022] Open
Abstract
Continuous Spontaneous Localization (CSL) is one possible explanation for dynamically induced collapse of the wave-function during a quantum measurement. The collapse is mediated by a stochastic non-linear modification of the Schrödinger equation. A consequence of the CSL mechanism is an extremely tiny violation of energy-momentum conservation, which can, in principle, be detected in the laboratory via the random diffusion of a particle induced by the stochastic collapse mechanism. In a paper in 2003, Collett and Pearle investigated the translational CSL diffusion of a sphere, and the rotational CSL diffusion of a disc, and showed that this effect dominates over the ambient environmental noise at low temperatures and extremely low pressures (about ten-thousandth of a pico-Torr). In the present paper, we revisit their analysis and argue that this stringent condition on pressure can be relaxed, and that the CSL effect can be seen at the pressure of about a pico-Torr. A similar analysis is provided for diffusion produced by gravity-induced decoherence, where the effect is typically much weaker than CSL. We also discuss the CSL induced random displacement of a quantum oscillator. Lastly, we propose possible experimental set-ups justifying that CSL diffusion is indeed measurable with the current technology.
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Affiliation(s)
- Sayantani Bera
- Tata Institute of Fundamental Research Homi Bhabha Road Mumbai 400005 India
| | - Bhawna Motwani
- Department of Physics Indian Institute of Technology Roorkee 247667 India
| | - Tejinder P Singh
- Tata Institute of Fundamental Research Homi Bhabha Road Mumbai 400005 India
| | - Hendrik Ulbricht
- School of Physics and Astronomy University of Southampton SO17 1BJ UK
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38
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Sezer U, Schmid P, Felix L, Mayor M, Arndt M. Stability of high-mass molecular libraries: the role of the oligoporphyrin core. JOURNAL OF MASS SPECTROMETRY : JMS 2015; 50:235-239. [PMID: 25601698 PMCID: PMC4322477 DOI: 10.1002/jms.3526] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 09/19/2014] [Accepted: 10/13/2014] [Indexed: 06/04/2023]
Abstract
Molecular beam techniques are a key to many experiments in physical chemistry and quantum optics. In particular, advanced matter-wave experiments with high-mass molecules profit from the availability of slow, neutral and mass-selected molecular beams that are sufficiently stable to remain intact during laser heating and photoionization mass spectrometry. We present experiments on the photostability with molecular libraries of tailored oligoporphyrins with masses up to 25,000 Da. We compare two fluoroalkylsulfanyl-functionalized libraries based on two different molecular cores that offer the same number of anchor points for functionalization but differ in their geometry and electronic properties. A pentaporphyrin core stabilizes a library of chemically well-defined molecules with more than 1600 atoms. They can be neutrally desorbed with velocities as low as 20 m/s and efficiently analyzed in photoionization mass spectrometry.
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Affiliation(s)
- Uĝur Sezer
- University of Vienna, Faculty of Physics, VCQ and QuNaBioSBoltzmanngasse 5, 1090, Vienna, Austria
| | - Philipp Schmid
- University of Vienna, Faculty of Physics, VCQ and QuNaBioSBoltzmanngasse 5, 1090, Vienna, Austria
| | - Lukas Felix
- Department of Chemistry, University of BaselSt. Johannsring 19, 4056, Basel, Switzerland
| | - Marcel Mayor
- Department of Chemistry, University of BaselSt. Johannsring 19, 4056, Basel, Switzerland
- Karlsruhe Institute of Technology (KIT), Institute of NanotechnologyP.O. Box 3640, 76021, Karlsruhe
| | - Markus Arndt
- University of Vienna, Faculty of Physics, VCQ and QuNaBioSBoltzmanngasse 5, 1090, Vienna, Austria
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39
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Araújo M, Costa F, Brukner Č. Computational advantage from quantum-controlled ordering of gates. PHYSICAL REVIEW LETTERS 2014; 113:250402. [PMID: 25554864 DOI: 10.1103/physrevlett.113.250402] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2014] [Indexed: 06/04/2023]
Abstract
It is usually assumed that a quantum computation is performed by applying gates in a specific order. One can relax this assumption by allowing a control quantum system to switch the order in which the gates are applied. This provides a more general kind of quantum computing that allows transformations on blackbox quantum gates that are impossible in a circuit with fixed order. Here we show that this model of quantum computing is physically realizable, by proposing an interferometric setup that can implement such a quantum control of the order between the gates. We show that this new resource provides a reduction in computational complexity: we propose a problem that can be solved by using O(n) blackbox queries, whereas the best known quantum algorithm with fixed order between the gates requires O(n^{2}) queries. Furthermore, we conjecture that solving this problem in a classical computer takes exponential time, which may be of independent interest.
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Affiliation(s)
- Mateus Araújo
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria and Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna, Austria
| | - Fabio Costa
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria and Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna, Austria
| | - Časlav Brukner
- Faculty of Physics, University of Vienna, Boltzmanngasse 5, 1090 Vienna, Austria and Institute for Quantum Optics and Quantum Information (IQOQI), Austrian Academy of Sciences, Boltzmanngasse 3, 1090 Vienna, Austria
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40
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Dörre N, Rodewald J, Geyer P, von Issendorff B, Haslinger P, Arndt M. Photofragmentation beam splitters for matter-wave interferometry. PHYSICAL REVIEW LETTERS 2014; 113:233001. [PMID: 25526125 DOI: 10.1103/physrevlett.113.233001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Indexed: 06/04/2023]
Abstract
Extending the range of quantum interferometry to a wider class of composite nanoparticles requires new tools to diffract matter waves. Recently, pulsed photoionization light gratings have demonstrated their suitability for high mass matter-wave physics. Here, we extend quantum interference experiments to a new class of particles by introducing photofragmentation beam splitters into time-domain matter-wave interferometry. We present data that demonstrate this coherent beam splitting mechanism with clusters of hexafluorobenzene and we show single-photon depletion gratings based both on fragmentation and ionization for clusters of vanillin. We propose that photofragmentation gratings can act on a large set of van der Waals clusters and biomolecules which are thermally unstable and often resilient to single-photon ionization.
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Affiliation(s)
- Nadine Dörre
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Jonas Rodewald
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Philipp Geyer
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Bernd von Issendorff
- University of Freiburg, Faculty of Physics, Stefan-Meier-Strasse 21, D-79104 Freiburg, Germany
| | - Philipp Haslinger
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Markus Arndt
- University of Vienna, Faculty of Physics, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
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41
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42
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Bateman J, Nimmrichter S, Hornberger K, Ulbricht H. Near-field interferometry of a free-falling nanoparticle from a point-like source. Nat Commun 2014; 5:4788. [DOI: 10.1038/ncomms5788] [Citation(s) in RCA: 127] [Impact Index Per Article: 12.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Accepted: 07/24/2014] [Indexed: 11/09/2022] Open
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43
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Eibenberger S, Cheng X, Cotter JP, Arndt M. Absolute absorption cross sections from photon recoil in a matter-wave interferometer. PHYSICAL REVIEW LETTERS 2014; 112:250402. [PMID: 25014795 DOI: 10.1103/physrevlett.112.250402] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/21/2014] [Indexed: 06/03/2023]
Abstract
We measure the absolute absorption cross section of molecules using a matter-wave interferometer. A nanostructured density distribution is imprinted onto a dilute molecular beam through quantum interference. As the beam crosses the light field of a probe laser some molecules will absorb a single photon. These absorption events impart a momentum recoil which shifts the position of the molecule relative to the unperturbed beam. Averaging over the shifted and unshifted components within the beam leads to a reduction of the fringe visibility, enabling the absolute absorption cross section to be extracted with high accuracy. This technique is independent of the molecular density, it is minimally invasive and successfully eliminates many problems related to photon cycling, state mixing, photobleaching, photoinduced heating, fragmentation, and ionization. It can therefore be extended to a wide variety of neutral molecules, clusters, and nanoparticles.
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Affiliation(s)
- Sandra Eibenberger
- Faculty of Physics, University of Vienna, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Xiaxi Cheng
- Faculty of Physics, University of Vienna, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - J P Cotter
- Faculty of Physics, University of Vienna, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
| | - Markus Arndt
- Faculty of Physics, University of Vienna, VCQ & QuNaBioS, Boltzmanngasse 5, A-1090 Vienna, Austria
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44
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Bassi A, Dürr D, Hinrichs G. Uniqueness of the equation for quantum state vector collapse. PHYSICAL REVIEW LETTERS 2013; 111:210401. [PMID: 24313467 DOI: 10.1103/physrevlett.111.210401] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2013] [Revised: 09/02/2013] [Indexed: 06/02/2023]
Abstract
The linearity of quantum mechanics leads, under the assumption that the wave function offers a complete description of reality, to grotesque situations famously known as Schrödinger's cat. Ways out are either adding elements of reality or replacing the linear evolution by a nonlinear one. Models of spontaneous wave function collapses took the latter path. The way such models are constructed leaves the question of whether such models are in some sense unique, i.e., whether the nonlinear equations replacing Schrödinger's equation are uniquely determined as collapse equations. Various people worked on identifying the class of nonlinear modifications of the Schrödinger equation, compatible with general physical requirements. Here we identify the most general class of continuous wave function evolutions under the assumption of no-faster-than-light signaling.
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Affiliation(s)
- Angelo Bassi
- Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste, Italy and Istituto Nazionale di Fisica Nucleare, Trieste Section, Via Valerio 2, 34127 Trieste, Italy
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