1
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Doran I, Hölsch N, Beyer M, Merkt F. Zero-Quantum-Defect Method and the Fundamental Vibrational Interval of H_{2}^{+}. PHYSICAL REVIEW LETTERS 2024; 132:073001. [PMID: 38427875 DOI: 10.1103/physrevlett.132.073001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Revised: 12/29/2023] [Accepted: 01/12/2024] [Indexed: 03/03/2024]
Abstract
The fundamental vibrational interval of H_{2}^{+} has been determined to be ΔG_{1/2}=2191.126 614(17) cm^{-1} by continuous-wave laser spectroscopy of Stark manifolds of Rydberg states of H_{2} with the H_{2}^{+} ion core in the ground and first vibrationally excited states. Extrapolation of the Stark shifts to zero field yields the zero-quantum-defect positions -R_{H_{2}}/n^{2}, from which ionization energies can be determined. Our new result represents a 4-order-of-magnitude improvement compared to earlier measurements. It agrees, within the experimental uncertainty, with the value of 2191.126 626 344(17)(100) cm^{-1} determined in nonrelativistic quantum electrodynamic calculations [V. Korobov, L. Hilico and J.-Ph. Karr, Phys. Rev. Lett. 118, 233001 (2017)PRLTAO0031-900710.1103/PhysRevLett.118.233001].
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Affiliation(s)
- I Doran
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - N Hölsch
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - M Beyer
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - F Merkt
- Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
- Department of Physics, ETH Zurich, Zurich, Switzerland
- Quantum Center, ETH Zurich, Zurich, Switzerland
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2
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Liu QH, Tan Y, Cheng CF, Hu SM. Precision spectroscopy of molecular hydrogen. Phys Chem Chem Phys 2023; 25:27914-27925. [PMID: 37843424 DOI: 10.1039/d3cp03042c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2023]
Abstract
Precision measurements on the hydrogen molecule are of fundamental importance in understanding molecular theory. Comparison of accurate experimental data and theoretical results are used to test the quantum electrodynamics theory and determine physical constants used in the calculation. We review recent advances and perspectives in the precision spectroscopy of molecular hydrogen, representing state-of-the-art molecular spectroscopy methods and cutting-edge high-precision calculations.
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Affiliation(s)
- Qian-Hao Liu
- Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
| | - Yan Tan
- Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
| | - Cun-Feng Cheng
- Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
| | - Shui-Ming Hu
- Department of Chemical Physics, University of Science and Technology of China, Hefei, 230026, China.
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3
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Schwegler N, Holzapfel D, Stadler M, Mitjans A, Sergachev I, Home JP, Kienzler D. Trapping and Ground-State Cooling of a Single H_{2}^{+}. PHYSICAL REVIEW LETTERS 2023; 131:133003. [PMID: 37831997 DOI: 10.1103/physrevlett.131.133003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 04/24/2023] [Accepted: 07/24/2023] [Indexed: 10/15/2023]
Abstract
We demonstrate co-trapping and sideband cooling of a H_{2}^{+}-^{9}Be^{+} ion pair in a cryogenic Paul trap. We study the chemical lifetime of H_{2}^{+} and its dependence on the apparatus temperature, achieving lifetimes of up to 11_{-3}^{+6} h at 10 K. We demonstrate cooling of two of the modes of translational motion to an average phonon number of 0.07(1) and 0.05(1), corresponding to a temperature of 22(1) and 55(3) μK, respectively. Our results provide a basis for quantum logic spectroscopy experiments of H_{2}^{+}, as well as other light ions such as HD^{+}, H_{3}^{+}, and He^{+}.
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Affiliation(s)
- N Schwegler
- Institute for Quantum Electronics, Department of Physics, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 1, 8093 Zurich, Switzerland
| | - D Holzapfel
- Institute for Quantum Electronics, Department of Physics, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 1, 8093 Zurich, Switzerland
| | - M Stadler
- Institute for Quantum Electronics, Department of Physics, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 1, 8093 Zurich, Switzerland
| | - A Mitjans
- Institute for Quantum Electronics, Department of Physics, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 1, 8093 Zurich, Switzerland
| | - I Sergachev
- Institute for Quantum Electronics, Department of Physics, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 1, 8093 Zurich, Switzerland
| | - J P Home
- Institute for Quantum Electronics, Department of Physics, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 1, 8093 Zurich, Switzerland
| | - D Kienzler
- Institute for Quantum Electronics, Department of Physics, Eidgenössische Technische Hochschule Zürich, Otto-Stern-Weg 1, 8093 Zurich, Switzerland
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4
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Jungen C. The fine and hyperfine structures of the low- n 3Π u Rydberg states of H 2 revisited. Mol Phys 2022. [DOI: 10.1080/00268976.2022.2152396] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Christian Jungen
- Department of Physics and Astronomy, University College London, London, UK
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5
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Qu Q, Yurchenko SN, Tennyson J. A Method for the Variational Calculation of Hyperfine-Resolved Rovibronic Spectra of Diatomic Molecules. J Chem Theory Comput 2022; 18:1808-1820. [PMID: 35148098 PMCID: PMC9097294 DOI: 10.1021/acs.jctc.1c01244] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2021] [Indexed: 11/29/2022]
Abstract
An algorithm for the calculation of hyperfine structure and spectra of diatomic molecules based on the variational nuclear motion is presented. The hyperfine coupling terms considered are Fermi-contact, nuclear spin-electron spin dipole-dipole, nuclear spin-orbit, nuclear spin-rotation, and nuclear electric quadrupole interactions. Initial hyperfine-unresolved wave functions are obtained for a given set of potential energy curves and associated couplings by a variation solution of the nuclear-motion Schrödinger equation. Fully hyperfine-resolved parity-conserved rovibronic Hamiltonian matrices for a given final angular momentum, F, are constructed and then diagonalized to give hyperfine-resolved energies and wave functions. Electric transition dipole moment curves can then be used to generate a hyperfine-resolved line list by applying rigorous selection rules. The algorithm is implemented in Duo, which is a general program for calculating spectra of diatomic molecules. This approach is tested for NO and MgH, and the results are compared to experiment and shown to be consistent with those given by the well-used effective Hamiltonian code PGOPHER.
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Affiliation(s)
- Qianwei Qu
- Department of Physics and
Astronomy, University College London, WC1E 6BT London, U.K.
| | - Sergei N. Yurchenko
- Department of Physics and
Astronomy, University College London, WC1E 6BT London, U.K.
| | - Jonathan Tennyson
- Department of Physics and
Astronomy, University College London, WC1E 6BT London, U.K.
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6
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Abstract
This article proposes a new method for sensing THz waves that can allow electric field measurements traceable to the International System of Units and to the fundamental physical constants by using the comparison between precision measurements with cold trapped HD+ ions and accurate predictions of molecular ion theory. The approach exploits the lightshifts induced on the two-photon rovibrational transition at 55.9 THz by a THz wave around 1.3 THz, which is off-resonantly coupled to the HD+ fundamental rotational transition. First, the direction and the magnitude of the static magnetic field applied to the ion trap is calibrated using Zeeman spectroscopy of HD+. Then, a set of lightshifts are converted into the amplitudes and the phases of the THz electric field components in an orthogonal laboratory frame by exploiting the sensitivity of the lightshifts to the intensity, the polarization and the detuning of the THz wave to the HD+ energy levels. The THz electric field measurement uncertainties are estimated for quantum projection noise-limited molecular ion frequency measurements with the current accuracy of molecular ion theory. The method has the potential to improve the sensitivity and accuracy of electric field metrology and may be extended to THz magnetic fields and to optical fields.
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7
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Alighanbari S, Giri GS, Constantin FL, Korobov VI, Schiller S. Precise test of quantum electrodynamics and determination of fundamental constants with HD+ ions. Nature 2020; 581:152-158. [DOI: 10.1038/s41586-020-2261-5] [Citation(s) in RCA: 62] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2018] [Accepted: 02/12/2020] [Indexed: 11/09/2022]
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8
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Beyer M, Hölsch N, Hussels J, Cheng CF, Salumbides EJ, Eikema KSE, Ubachs W, Jungen C, Merkt F. Determination of the Interval between the Ground States of Para- and Ortho-H_{2}. PHYSICAL REVIEW LETTERS 2019; 123:163002. [PMID: 31702363 DOI: 10.1103/physrevlett.123.163002] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/18/2019] [Indexed: 06/10/2023]
Abstract
Nuclear-spin-symmetry conservation makes the observation of transitions between quantum states of ortho- and para-H_{2} extremely challenging. Consequently, the energy-level structure of H_{2} derived from experiment consists of two disjoint sets of level energies, one for para-H_{2} and the other for ortho-H_{2}. We use a new measurement of the ionization energy of para-H_{2} [E_{I}(H_{2})/(hc)=124 417.491 098(31) cm^{-1}] to determine the energy separation [118.486 770(50) cm^{-1}] between the ground states of para- and ortho-H_{2} and thus link the energy-level structure of the two nuclear-spin isomers of this fundamental molecule. Comparison with recent theoretical results [M. Puchalski et al., Phys. Rev. Lett. 122, 103003 (2019)PRLTAO0031-900710.1103/PhysRevLett.122.103003] enables the derivation of an upper bound of 1.5 MHz for a hypothetical global shift of the energy-level structure of ortho-H_{2} with respect to that of para-H_{2}.
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Affiliation(s)
- M Beyer
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - N Hölsch
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - J Hussels
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - C-F Cheng
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - E J Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - K S E Eikema
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - W Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - Ch Jungen
- Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - F Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
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9
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Hölsch N, Beyer M, Salumbides EJ, Eikema KSE, Ubachs W, Jungen C, Merkt F. Benchmarking Theory with an Improved Measurement of the Ionization and Dissociation Energies of H_{2}. PHYSICAL REVIEW LETTERS 2019; 122:103002. [PMID: 30932670 DOI: 10.1103/physrevlett.122.103002] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Revised: 01/29/2019] [Indexed: 06/09/2023]
Abstract
The dissociation energy of H_{2} represents a benchmark quantity to test the accuracy of first-principles calculations. We present a new measurement of the energy interval between the EF ^{1}Σ_{g}^{+}(v=0,N=1) state and the 54p1_{1} Rydberg state of H_{2}. When combined with previously determined intervals, this new measurement leads to an improved value of the dissociation energy D_{0}^{N=1} of ortho-H_{2} that has, for the first time, reached a level of uncertainty that is 3 times smaller than the contribution of about 1 MHz resulting from the finite size of the proton. The new result of 35 999.582 834(11) cm^{-1} is in remarkable agreement with the theoretical result of 35 999.582 820(26) cm^{-1} obtained in calculations including high-order relativistic and quantum-electrodynamics corrections, as reported in the following Letter [M. Puchalski, J. Komasa, P. Czachorowski, and K. Pachucki, Phys. Rev. Lett. 122, 103003 (2019)PRLTAO0031-900710.1103/PhysRevLett.122.103003]. This agreement resolves a recent discrepancy between experiment and theory that had hindered a possible use of the dissociation energy of H_{2} in the context of the current controversy on the charge radius of the proton.
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Affiliation(s)
- Nicolas Hölsch
- Laboratorium für Physikalische Chemie, ETH-Zürich, 8093 Zürich, Switzerland
| | - Maximilian Beyer
- Laboratorium für Physikalische Chemie, ETH-Zürich, 8093 Zürich, Switzerland
| | - Edcel J Salumbides
- LaserLaB, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Kjeld S E Eikema
- LaserLaB, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Wim Ubachs
- LaserLaB, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Christian Jungen
- Department of Physics and Astronomy, University College London, London, WC1E 6BT United Kingdom
| | - Frédéric Merkt
- Laboratorium für Physikalische Chemie, ETH-Zürich, 8093 Zürich, Switzerland
- LaserLaB, Department of Physics and Astronomy, Vrije Universiteit, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
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10
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Beutner V, Duffy LM, Meyer H. Resonance Enhanced Multiphoton Ionization Detected Millimeter-Wave Absorption: The 115 GHz Line of CO. J Phys Chem A 2019; 123:2153-2162. [DOI: 10.1021/acs.jpca.8b11528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- V. Beutner
- Department of Physics and Astronomy, The University of Georgia, Athens, Georgia 30602-2451, United States
| | - L. M. Duffy
- Department of Chemistry & Biochemistry, University of North Carolina at Greensboro, Greensboro, North Carolina 27412, United States
| | - H. Meyer
- Department of Physics and Astronomy, The University of Georgia, Athens, Georgia 30602-2451, United States
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11
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Beyer M, Merkt F. Hyperfine-interaction-induced g/u mixing and its implication on the existence of the first excited vibrational level of the A + Σ u + 2 state of H 2 + and on the scattering length of the H + H + collision. J Chem Phys 2018; 149:214301. [PMID: 30525720 DOI: 10.1063/1.5046147] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Ab initio calculations of the energy level structure of H 2 + that include relativistic and radiative corrections to nonrelativistic energies and the diagonal part of the hyperfine interaction have predicted the existence of four bound rovibrational levels [(v = 0, N = 0 - 2) and (v = 1, N = 0)] of the first electronically excited ( A + Σ u + 2 ) state of H 2 + , the (v = 1, N = 0) level having a calculated binding energy of only E b = 1.082 219 8(4)·10-9 Eh and leading to an extremely large scattering length of 750(5) a0 for the H+ + H collision [J. Carbonell et al., J. Phys. B: At., Mol. Opt. Phys. 37, 2997 (2004)]. We present an investigation of the nonadiabatic coupling between the first two electronic states ( X + Σ g + 2 and A + Σ u + 2 ) of H 2 + induced by the Fermi-contact term of the hyperfine-coupling Hamiltonian. This interaction term, which mixes states of total spin quantum number G = 1/2, is rigorously implemented in a close-coupling approach to solve the spin-rovibronic Schrödinger equation. We show that it mixes states of gerade and ungerade electronic symmetry, that it shifts the positions of all weakly bound rovibrational states of H 2 + , and that it affects both the positions and widths of its shape resonances. The calculations demonstrate that the G = 1/2 hyperfine component of the A+ (v = 1, N = 0) state does not exist and that, for G = 1/2, the s-wave scattering lengths of the H+ + H(1s) collision are -578(6) a0 and -43(4) a0 for the F = 0 and F = 1 hyperfine components of the H(1s) atom, respectively. The binding energy of the G = 3/2 hyperfine component of the A+ (v = 1, N = 0) state is not significantly affected by the hyperfine interaction and the corresponding scattering length for the H+ + H(1s, F = 1) collision is 757(7) a0.
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Affiliation(s)
- Maximilian Beyer
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - Frédéric Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
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12
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Hölsch N, Beyer M, Merkt F. Nonadiabatic effects on the positions and lifetimes of the low-lying rovibrational levels of the GK 1Σ and H 1Σ states of H 2. Phys Chem Chem Phys 2018; 20:26837-26845. [PMID: 30328429 DOI: 10.1039/c8cp05233f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The term values of rovibrational levels of the GK 1Σ+g and H 1Σ+g states of H2 have been measured with absolute and relative accuracies down to 10-4 cm-1 (≈3 MHz) and 10-6 cm-1 (≈30 kHz), respectively, by measuring transitions to long-lived high-n Rydberg states using single-mode cw laser radiation and a collimated supersonic beam of cold H2 molecules. The term values are compared with those determined in earlier experimental and theoretical investigations and the comparison points at discrepancies and a need for improved theoretical treatments of nonadiabatic, relativistic and radiative corrections for these states. The lifetimes of several low-lying rovibrational levels of the GK, H and I+ 1Πg states have been determined in pump-probe experiments. These lifetimes reveal a significant dependence on the electronic, vibrational and rotational excitation and also deviate from results obtained in earlier experimental and theoretical investigations.
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Affiliation(s)
- Nicolas Hölsch
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland.
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13
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Cheng CF, Hussels J, Niu M, Bethlem HL, Eikema KSE, Salumbides EJ, Ubachs W, Beyer M, Hölsch N, Agner JA, Merkt F, Tao LG, Hu SM, Jungen C. Dissociation Energy of the Hydrogen Molecule at 10^{-9} Accuracy. PHYSICAL REVIEW LETTERS 2018; 121:013001. [PMID: 30028156 DOI: 10.1103/physrevlett.121.013001] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Indexed: 06/08/2023]
Abstract
The ionization energy of ortho-H_{2} has been determined to be E_{I}^{o}(H_{2})/(hc)=124 357.238 062(25) cm^{-1} from measurements of the GK(1,1)-X(0,1) interval by Doppler-free, two-photon spectroscopy using a narrow band 179-nm laser source and the ionization energy of the GK(1,1) state by continuous-wave, near-infrared laser spectroscopy. E_{I}^{o}(H_{2}) was used to derive the dissociation energy of H_{2}, D_{0}^{N=1}(H_{2}), at 35 999.582 894(25) cm^{-1} with a precision that is more than one order of magnitude better than all previous results. The new result challenges calculations of this quantity and represents a benchmark value for future relativistic and QED calculations of molecular energies.
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Affiliation(s)
- C-F Cheng
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - J Hussels
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - M Niu
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - H L Bethlem
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - K S E Eikema
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - E J Salumbides
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - W Ubachs
- Department of Physics and Astronomy, LaserLaB, Vrije Universiteit Amsterdam, de Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - M Beyer
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - N Hölsch
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - J A Agner
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - F Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - L-G Tao
- Hefei National Laboratory for Physical Sciences at Microscale, iChem center, University of Science and Technology China, Hefei, 230026 China
| | - S-M Hu
- Hefei National Laboratory for Physical Sciences at Microscale, iChem center, University of Science and Technology China, Hefei, 230026 China
| | - Ch Jungen
- Laboratoire Aimé Cotton du CNRS, Bâtiment 505, Université de Paris-Sud, F-91405 Orsay, France and Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
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14
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Altmann RK, Dreissen LS, Salumbides EJ, Ubachs W, Eikema KSE. Deep-Ultraviolet Frequency Metrology of H_{2} for Tests of Molecular Quantum Theory. PHYSICAL REVIEW LETTERS 2018; 120:043204. [PMID: 29437464 DOI: 10.1103/physrevlett.120.043204] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Indexed: 06/08/2023]
Abstract
Molecular hydrogen and its isotopic and ionic species are benchmark systems for testing quantum chemical theory. Advances in molecular energy structure calculations enable the experimental verification of quantum electrodynamics and potentially a determination of the proton charge radius from H_{2} spectroscopy. We measure the ground state energy in ortho-H_{2} relative to the first electronically excited state by Ramsey-comb laser spectroscopy on the EF^{1}Σ_{g}^{+}-X^{1}Σ_{g}^{+}(0,0) Q1 transition. The resulting transition frequency of 2 971 234 992 965(73) kHz is 2 orders of magnitude more accurate than previous measurements. This paves the way for a considerably improved determination of the dissociation energy (D_{0}) for fundamental tests with molecular hydrogen.
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Affiliation(s)
- R K Altmann
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - L S Dreissen
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - E J Salumbides
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - W Ubachs
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - K S E Eikema
- LaserLaB, Department of Physics and Astronomy, VU University Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
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15
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Jansen P, Semeria L, Merkt F. Determination of the Spin-Rotation Fine Structure of He_{2}^{+}. PHYSICAL REVIEW LETTERS 2018; 120:043001. [PMID: 29437449 DOI: 10.1103/physrevlett.120.043001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2017] [Indexed: 06/08/2023]
Abstract
Measuring spin-rotation intervals in molecular cations is challenging, particularly so when the ions do not have electric-dipole-allowed rovibrational transitions. We present a method, based on an angular-momentum basis transformation, to determine the spin-rotational fine structure of molecular ions from the fine structure of high Rydberg states. The method is illustrated by the determination of the so far unknown spin-rotation fine structure of the fundamentally important He_{2}^{+} ion in the X ^{2}Σ_{u}^{+} state. The fine-structure splittings of the v^{+}=0, N^{+}=1, 3, and 5 levels of He_{2}^{+} are 7.96(14), 17.91(32), and 28.0(6) MHz, respectively. The experiment relies on the use of single-mode cw radiation to record spectra of high Rydberg states of He_{2} from the a ^{3}Σ_{u}^{+} metastable state.
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Affiliation(s)
- Paul Jansen
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Luca Semeria
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Frédéric Merkt
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
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16
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Quiros N, Tariq N, Tscherbul TV, Kłos J, Weinstein JD. Cold Anisotropically Interacting van der Waals Molecule: TiHe. PHYSICAL REVIEW LETTERS 2017; 118:213401. [PMID: 28598640 DOI: 10.1103/physrevlett.118.213401] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2017] [Indexed: 06/07/2023]
Abstract
We have used laser ablation and helium buffer-gas cooling to produce titanium-helium van der Waals molecules at cryogenic temperatures. The molecules were detected through laser-induced fluorescence spectroscopy. Ground-state Ti(a^{3}F_{2})-He binding energies were determined for the ground and first rotationally excited states from studying equilibrium thermodynamic properties, and found to agree well with theoretical calculations based on newly calculated ab initio Ti-He interaction potentials, opening up novel possibilities for studying the formation, dynamics, and nonuniversal chemistry of van der Waals clusters at low temperatures.
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Affiliation(s)
- Nancy Quiros
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - Naima Tariq
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - Timur V Tscherbul
- Department of Physics, University of Nevada, Reno, Nevada 89557, USA
| | - Jacek Kłos
- Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA
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17
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Semeria L, Jansen P, Merkt F. Precision measurement of the rotational energy-level structure of the three-electron molecule He 2. J Chem Phys 2016; 145:204301. [PMID: 27908106 DOI: 10.1063/1.4967256] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The term values of all rotational levels of the 4He2+ X+ 2Σu+ (ν+=0) ground vibronic state with rotational quantum number N+ ≤ 19 have been determined with an accuracy of 8 × 10-4 cm-1 (∼25 MHz) by multichannel-quantum-defect-theory-assisted Rydberg spectroscopy of metastable He2∗. Comparison of these term values with term values recently calculated ab initio by Tung et al. [J. Chem. Phys. 136, 104309 (2012)] reveals discrepancies that rapidly increase with increasing rotational quantum number and reach values of 0.07 cm-1 (∼2.1 GHz) at N+ = 19.
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Affiliation(s)
- Luca Semeria
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Paul Jansen
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Frédéric Merkt
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
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18
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Germann M, Willitsch S. Fine- and hyperfine-structure effects in molecular photoionization. I. General theory and direct photoionization. J Chem Phys 2016; 145:044314. [DOI: 10.1063/1.4955301] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Affiliation(s)
- Matthias Germann
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
| | - Stefan Willitsch
- Department of Chemistry, University of Basel, Klingelbergstrasse 80, 4056 Basel, Switzerland
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19
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Beyer M, Merkt F. Observation and Calculation of the Quasibound Rovibrational Levels of the Electronic Ground State of H2+. PHYSICAL REVIEW LETTERS 2016; 116:093001. [PMID: 26991172 DOI: 10.1103/physrevlett.116.093001] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/17/2015] [Indexed: 06/05/2023]
Abstract
Although the existence of quasibound rotational levels of the X^{+} ^{2}Σ_{g}^{+} ground state of H_{2}^{+} was predicted a long time ago, these states have never been observed. Calculated positions and widths of quasibound rotational levels located close to the top of the centrifugal barriers have not been reported either. Given the role that such states play in the recombination of H(1s) and H^{+} to form H_{2}^{+}, this lack of data may be regarded as one of the largest unknown aspects of this otherwise accurately known fundamental molecular cation. We present measurements of the positions and widths of the lowest-lying quasibound rotational levels of H_{2}^{+} and compare the experimental results with the positions and widths we calculate using a potential model for the X^{+} state of H_{2}^{+} which includes adiabatic, nonadiabatic, relativistic, and radiative corrections to the Born-Oppenheimer approximation.
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Affiliation(s)
- Maximilian Beyer
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
| | - Frédéric Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich, 8093 Zürich, Switzerland
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20
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Hogan SD. Rydberg-Stark deceleration of atoms and molecules. EPJ TECHNIQUES AND INSTRUMENTATION 2016; 3:2. [PMID: 32355605 PMCID: PMC7175735 DOI: 10.1140/epjti/s40485-015-0028-4] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 12/27/2015] [Indexed: 06/06/2023]
Abstract
The large electric dipole moments associated with highly excited Rydberg states of atoms and molecules make gas-phase samples in these states very well suited to deceleration and trapping using inhomogeneous electric fields. The methods of Rydberg-Stark deceleration with which this can be achieved are reviewed here. Using these techniques, the longitudinal motion of beams of atoms and molecules moving at speeds as high as 2500 m/s have been manipulated, with changes in kinetic energy of up to |Δ E kin|=1.3×10-20 J (|Δ E kin|/e=80 meV or |Δ E kin|/h c=650 cm -1) achieved, while decelerated and trapped samples with number densities of 106- 107 cm -3 and translational temperatures of ∼150 mK have been prepared. Applications of these samples in areas of research at the interface between physics and physical chemistry are discussed.
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Affiliation(s)
- Stephen D. Hogan
- Department of Physics and Astronomy, University College London, Gower Street, London, WC1E 6BT UK
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21
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Korobov VI, Koelemeij JCJ, Hilico L, Karr JP. Theoretical Hyperfine Structure of the Molecular Hydrogen Ion at the 1 ppm Level. PHYSICAL REVIEW LETTERS 2016; 116:053003. [PMID: 26894709 DOI: 10.1103/physrevlett.116.053003] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2015] [Indexed: 06/05/2023]
Abstract
We revisit the mα^{6}(m/M) order corrections to the hyperfine splitting in the H_{2}^{+} ion and find a hitherto unrecognized second-order relativistic contribution associated with the vibrational motion of the nuclei. Inclusion of this correction term produces theoretical predictions which are in excellent agreement with experimental data [K. B. Jefferts, Phys. Rev. Lett. 23, 1476 (1969)], thereby concluding a nearly 50-year-long theoretical quest to explain the experimental results within their 1-ppm error. The agreement between the theory and experiment corroborates the proton structural properties as derived from the hyperfine structure of atomic hydrogen. Our work furthermore indicates that, for future improvements, a full three-body evaluation of the mα^{6}(m/M) correction term will be mandatory.
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Affiliation(s)
- Vladimir I Korobov
- Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, Dubna 141980, Russia
| | - J C J Koelemeij
- LaserLaB and Department of Physics and Astronomy, VU University, De Boelelaan 1081, 1081 HV Amsterdam, Netherlands
| | - L Hilico
- Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University, Collège de France, 4 place Jussieu, F-75005 Paris, France and Université d'Evry-Val d'Essonne, Boulevard François Mitterrand, F-91000 Evry, France
| | - J-Ph Karr
- Laboratoire Kastler Brossel, UPMC-Sorbonne Universités, CNRS, ENS-PSL Research University, Collège de France, 4 place Jussieu, F-75005 Paris, France and Université d'Evry-Val d'Essonne, Boulevard François Mitterrand, F-91000 Evry, France
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22
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Jansen P, Semeria L, Hofer LE, Scheidegger S, Agner JA, Schmutz H, Merkt F. Precision Spectroscopy in Cold Molecules: The Lowest Rotational Interval of He_{2}^{+} and Metastable He_{2}. PHYSICAL REVIEW LETTERS 2015; 115:133202. [PMID: 26451553 DOI: 10.1103/physrevlett.115.133202] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Indexed: 06/05/2023]
Abstract
Multistage Zeeman deceleration was used to generate a slow, dense beam of translationally cold He_{2} molecules in the metastable a ^{3}Σ_{u}^{+} state. Precision measurements of the Rydberg spectrum of these molecules at high values of the principal quantum number n have been carried out. The spin-rotational state selectivity of the Zeeman-deceleration process was exploited to reduce the spectral congestion, minimize residual Doppler shifts, resolve the Rydberg series around n=200 and assign their fine structure. The ionization energy of metastable He_{2} and the lowest rotational interval of the X^{+} ^{2}Σ_{u}^{+} (ν^{+}=0) ground state of ^{4}He_{2}^{+} have been determined with unprecedented precision and accuracy by Rydberg-series extrapolation. Comparison with ab initio predictions of the rotational energy level structure of ^{4}He_{2}^{+} [W.-C. Tung, M. Pavanello, and L. Adamowicz, J. Chem. Phys. 136, 104309 (2012)] enabled us to quantify the magnitude of relativistic and quantum-electrodynamics contributions to the fundamental rotational interval of He_{2}^{+}.
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Affiliation(s)
- Paul Jansen
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Luca Semeria
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | | | - Simon Scheidegger
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Josef A Agner
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Hansjürg Schmutz
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
| | - Frédéric Merkt
- Laboratory of Physical Chemistry, ETH Zurich, CH-8093 Zurich, Switzerland
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23
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Haase C, Beyer M, Jungen C, Merkt F. The fundamental rotational interval of para-H2+ by MQDT-assisted Rydberg spectroscopy of H2. J Chem Phys 2015; 142:064310. [DOI: 10.1063/1.4907531] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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24
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Mezei JZ, Schneider IF, Glass-Maujean M, Jungen C. Resonances in photoabsorption: Predissociation line shapes in the 3pπDΠu+1←X1Σg+ system in H2. J Chem Phys 2014; 141:064305. [DOI: 10.1063/1.4891813] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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25
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Sashikesh G, So E, Ford M, Softley T. Surface ionisation of molecular H2 and atomic H Rydberg states at doped silicon surfaces. Mol Phys 2014. [DOI: 10.1080/00268976.2014.940022] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
- G. Sashikesh
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford, OX1 3TA, United Kingdom
| | - E. So
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford, OX1 3TA, United Kingdom
| | - M.S. Ford
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford, OX1 3TA, United Kingdom
| | - T.P. Softley
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Oxford, OX1 3TA, United Kingdom
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26
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Sprecher D, Merkt F. Observation of g/u-symmetry mixing in the high-n Rydberg states of HD. J Chem Phys 2014; 140:124313. [PMID: 24697447 DOI: 10.1063/1.4868024] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The structure and dynamics of high-n Rydberg states belonging to series converging to the (v(+) = 0, N(+) = 0-2) levels of the X(+) (2)Σ(g)(+)electronic ground state of HD(+) were studied by high-resolution spectroscopy from the GK (1)Σ(g)(+) (v = 1, N = 1) state under field-free conditions. Three effects of g/u-symmetry breaking were detected: (i) Single-photon transitions from the GK (v = 1, N = 1) state of gerade symmetry to the 30d21 and 31g22 Rydberg states of gerade symmetry were observed after careful compensation of the stray electric fields. (ii) The singlet 61p12 Rydberg state of ungerade symmetry was found to autoionize to the N(+) = 0, ℓ = 2 ionization continuum of gerade symmetry with a lifetime of 77(10) ns. (iii) Shifts of up to 20 MHz induced by g/u-symmetry mixing were measured for members of the np11 Rydberg series which lie close to nd21 Rydberg states. These observations were analyzed in the framework of multichannel quantum-defect theory. From the observed level shifts, the off-diagonal eigenquantum-defect element μ(pd) of singlet-π symmetry was determined to be 0.0023(3) and the corresponding autoionization dynamics could be characterized. The ionization energy of the GK (v = 1, N = 1) state of HD was determined to be 12 710.544 23(10) cm(-1).
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Affiliation(s)
- Daniel Sprecher
- Laboratorium für Physikalische Chemie, ETH-Zürich, 8093 Zürich, Switzerland
| | - Frédéric Merkt
- Laboratorium für Physikalische Chemie, ETH-Zürich, 8093 Zürich, Switzerland
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27
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Sprecher D, Jungen C, Merkt F. Determination of the binding energies of the np Rydberg states of H2, HD, and D2 from high-resolution spectroscopic data by multichannel quantum-defect theory. J Chem Phys 2014; 140:104303. [DOI: 10.1063/1.4866809] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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28
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Sprecher D, Liu J, Krähenmann T, Schäfer M, Merkt F. High-resolution spectroscopy and quantum-defect model for the gerade triplet np and nf Rydberg states of He2. J Chem Phys 2014; 140:064304. [DOI: 10.1063/1.4864002] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Haase C, Agner JA, Merkt F. High-resolution laser spectroscopy between 0.9 and 14.3 THz in a supersonic beam: Rydberg-Rydberg transitions of atomic Xe at intermediate n values. J Chem Phys 2013; 138:244202. [DOI: 10.1063/1.4809740] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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30
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Colombo AP, Zhou Y, Prozument K, Coy SL, Field RW. Chirped-pulse millimeter-wave spectroscopy: spectrum, dynamics, and manipulation of Rydberg-Rydberg transitions. J Chem Phys 2013; 138:014301. [PMID: 23298035 DOI: 10.1063/1.4772762] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023] Open
Abstract
We apply the chirped-pulse millimeter-wave (CPmmW) technique to transitions between Rydberg states in calcium atoms. The unique feature of Rydberg-Rydberg transitions is that they have enormous electric dipole transition moments (~5 kiloDebye at n* ~ 40, where n* is the effective principal quantum number), so they interact strongly with the mm-wave radiation. After polarization by a mm-wave pulse in the 70-84 GHz frequency region, the excited transitions re-radiate free induction decay (FID) at their resonant frequencies, and the FID is heterodyne-detected by the CPmmW spectrometer. Data collection and averaging are performed in the time domain. The spectral resolution is ~100 kHz. Because of the large transition dipole moments, the available mm-wave power is sufficient to polarize the entire bandwidth of the spectrometer (12 GHz) in each pulse, and high-resolution survey spectra may be collected. Both absorptive and emissive transitions are observed, and they are distinguished by the phase of their FID relative to that of the excitation pulse. With the combination of the large transition dipole moments and direct monitoring of transitions, we observe dynamics, such as transient nutations from the interference of the excitation pulse with the polarization that it induces in the sample. Since the waveform produced by the mm-wave source may be precisely controlled, we can populate states with high angular momentum by a sequence of pulses while recording the results of these manipulations in the time domain. We also probe the superradiant decay of the Rydberg sample using photon echoes. The application of the CPmmW technique to transitions between Rydberg states of molecules is discussed.
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Affiliation(s)
- Anthony P Colombo
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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31
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Sprecher D, Beyer M, Merkt F. Precision measurement of the ionisation energy of the 3dσ GK state of H2. Mol Phys 2013. [DOI: 10.1080/00268976.2013.788743] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- D. Sprecher
- Laboratorium für Physikalische Chemie, ETH Zürich , Zurich, Switzerland
| | - M. Beyer
- Laboratorium für Physikalische Chemie, ETH Zürich , Zurich, Switzerland
| | - F. Merkt
- Laboratorium für Physikalische Chemie, ETH Zürich , Zurich, Switzerland
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32
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Sprecher D, Jungen C, Merkt F. Spectrum of the Autoionizing Triplet Gerade Rydberg States of H2 and its Analysis Using Multichannel Quantum-Defect Theory. J Phys Chem A 2013; 117:9462-76. [DOI: 10.1021/jp311793t] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Daniel Sprecher
- Laboratory of Physical Chemistry, ETH Zürich, 8093 Zürich, Switzerland
| | - Christian Jungen
- Laboratoire Aimé Cotton
du CNRS, Université de Paris-Sud, 91405 Orsay, France
| | - Frédéric Merkt
- Laboratory of Physical Chemistry, ETH Zürich, 8093 Zürich, Switzerland
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33
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Park GB, Steeves AH, Kuyanov-Prozument K, Neill JL, Field RW. Design and evaluation of a pulsed-jet chirped-pulse millimeter-wave spectrometer for the 70–102 GHz region. J Chem Phys 2011; 135:024202. [DOI: 10.1063/1.3597774] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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34
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Affiliation(s)
- Ch Seiler
- ETH Zurich, Laboratory of Physical Chemistry, Wolfgang Pauli-Str. 10, Zurich, Switzerland
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35
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Sprecher D, Jungen C, Ubachs W, Merkt F. Towards measuring the ionisation and dissociation energies of molecular hydrogen with sub-MHz accuracy. Faraday Discuss 2011; 150:51-70; discussion 113-60. [DOI: 10.1039/c0fd00035c] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Kay JJ, Altunata SN, Coy SL, Field RW. Resonance between electronic and rotational motions in Rydberg states of CaF. Mol Phys 2010. [DOI: 10.1080/00268970701549371] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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37
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Sprecher D, Liu J, Jungen C, Ubachs W, Merkt F. Communication: The ionization and dissociation energies of HD. J Chem Phys 2010; 133:111102. [DOI: 10.1063/1.3483462] [Citation(s) in RCA: 61] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023] Open
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38
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Liu J, Sprecher D, Jungen C, Ubachs W, Merkt F. Determination of the ionization and dissociation energies of the deuterium molecule (D2). J Chem Phys 2010; 132:154301. [DOI: 10.1063/1.3374426] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
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39
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Vieitez MO, Ivanov TI, Reinhold E, de Lange CA, Ubachs W. Spectroscopic observation and characterization of H(+)H(-) heavy Rydberg states. J Phys Chem A 2009; 113:13237-45. [PMID: 19921940 DOI: 10.1021/jp9039918] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A series of discrete resonances was observed in the spectrum of H2, which can be unambiguously assigned to bound quantum states in the 1/R Coulombic potential of the H+H- ion-pair system. Two-step laser excitation was performed, using tunable extreme ultraviolet radiation at lambda = 94-96 nm in the first step, and tunable ultraviolet radiation in the range lambda = 310-350 nm in the second step. The resonances, detected via H+ and H2+ ions produced in the decay process, follow a sequence of principal quantum numbers (n = 140-230) associated with a Rydberg formula in which the Rydberg constant is mass scaled. The series converges upon the ionic H+H- dissociation threshold. This limit can be calculated without further assumptions from known ionization and dissociation energies in the hydrogen system and the electronegativity of the hydrogen atom. A possible excitation mechanism is discussed in terms of a complex resonance. Detailed measurements are performed to unravel and quantify the decay of the heavy Rydberg states into molecular H2+ ions, as well as into atomic fragments, both H(n = 2) and H(n = 3). Lifetimes are found to scale as n3.
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Affiliation(s)
- M O Vieitez
- Laser Centre, Vrije Universiteit, Amsterdam, Netherlands
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40
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Piszczatowski K, Łach G, Przybytek M, Komasa J, Pachucki K, Jeziorski B. Theoretical Determination of the Dissociation Energy of Molecular Hydrogen. J Chem Theory Comput 2009; 5:3039-48. [DOI: 10.1021/ct900391p] [Citation(s) in RCA: 149] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Konrad Piszczatowski
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warsaw, Poland, Center for Theoretical and Computational Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway, Faculty of Chemistry, A. Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland, and Institute of Theoretical Physics, University of Warsaw, Hoża 69, 00-681 Warsaw, Poland
| | - Grzegorz Łach
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warsaw, Poland, Center for Theoretical and Computational Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway, Faculty of Chemistry, A. Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland, and Institute of Theoretical Physics, University of Warsaw, Hoża 69, 00-681 Warsaw, Poland
| | - Michal Przybytek
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warsaw, Poland, Center for Theoretical and Computational Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway, Faculty of Chemistry, A. Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland, and Institute of Theoretical Physics, University of Warsaw, Hoża 69, 00-681 Warsaw, Poland
| | - Jacek Komasa
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warsaw, Poland, Center for Theoretical and Computational Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway, Faculty of Chemistry, A. Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland, and Institute of Theoretical Physics, University of Warsaw, Hoża 69, 00-681 Warsaw, Poland
| | - Krzysztof Pachucki
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warsaw, Poland, Center for Theoretical and Computational Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway, Faculty of Chemistry, A. Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland, and Institute of Theoretical Physics, University of Warsaw, Hoża 69, 00-681 Warsaw, Poland
| | - Bogumil Jeziorski
- Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093, Warsaw, Poland, Center for Theoretical and Computational Chemistry, University of Oslo, P.O. Box 1033 Blindern, N-0315 Oslo, Norway, Faculty of Chemistry, A. Mickiewicz University, Grunwaldzka 6, 60-780 Poznań, Poland, and Institute of Theoretical Physics, University of Warsaw, Hoża 69, 00-681 Warsaw, Poland
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41
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Hogan SD, Seiler C, Merkt F. Rydberg-state-enabled deceleration and trapping of cold molecules. PHYSICAL REVIEW LETTERS 2009; 103:123001. [PMID: 19792428 DOI: 10.1103/physrevlett.103.123001] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2009] [Indexed: 05/28/2023]
Abstract
Hydrogen molecules in selected core-nonpenetrating Rydberg-Stark states have been decelerated from a mean initial velocity of 500 m/s to zero velocity in the laboratory frame and loaded into a three-dimensional electrostatic trap. Trapping times, measured by pulsed electric field ionization of the trapped molecules, are found to be limited by collisional processes. As Rydberg states can be deexcited to the absolute ground state, the method can be applied to generate cold samples of a wide range of species.
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Affiliation(s)
- S D Hogan
- Laboratorium für Physikalische Chemie, ETH Zürich, CH-8093, Switzerland
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42
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Glass-Maujean M, Jungen C. Nonadiabatic Ab Initio Multichannel Quantum Defect Theory Applied to Absolute Experimental Absorption Intensities in H2. J Phys Chem A 2009; 113:13124-32. [DOI: 10.1021/jp902846c] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- M. Glass-Maujean
- Laboratoire de Physique Moléculaire pour l’Atmosphère et l’Astrophysique, Université Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05, France, Laboratoire Aimé Cotton du CNRS, Bâtiment 505, Université de Paris-Sud, F-91405 Orsay, France, and Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
| | - Ch. Jungen
- Laboratoire de Physique Moléculaire pour l’Atmosphère et l’Astrophysique, Université Pierre et Marie Curie, 4 place Jussieu, 75252 Paris Cedex 05, France, Laboratoire Aimé Cotton du CNRS, Bâtiment 505, Université de Paris-Sud, F-91405 Orsay, France, and Department of Physics and Astronomy, University College London, London WC1E 6BT, United Kingdom
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43
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Liu J, Salumbides EJ, Hollenstein U, Koelemeij JCJ, Eikema KSE, Ubachs W, Merkt F. Determination of the ionization and dissociation energies of the hydrogen molecule. J Chem Phys 2009; 130:174306. [DOI: 10.1063/1.3120443] [Citation(s) in RCA: 146] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
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Philippson JN, Shiell RC, Reinhold E, Ubachs W. Observation of molecular hyperfine structure in the extreme ultraviolet: The HF C-X spectrum. J Chem Phys 2008; 129:174310. [DOI: 10.1063/1.3006400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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45
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Vieitez MO, Ivanov TI, Reinhold E, de Lange CA, Ubachs W. Observation of a Rydberg series in H+H-: a heavy Bohr atom. PHYSICAL REVIEW LETTERS 2008; 101:163001. [PMID: 18999662 DOI: 10.1103/physrevlett.101.163001] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2008] [Indexed: 05/27/2023]
Abstract
We report on the realization of a heavy "Bohr atom," through the spectroscopic observation of a Rydberg series of bound quantum states at principal quantum numbers n=140 to 230. The system is made heavy by replacing an electron inside a hydrogen atom by a composite H- particle, thus forming a H+H- Coulombically bound system obeying the physical laws of a generalized atom with appropriate mass scaling.
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Affiliation(s)
- M O Vieitez
- Laser Centre, Vrije Universiteit, De Boelelaan 1081, Amsterdam, The Netherlands
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Kay JJ, Coy SL, Petrović VS, Wong BM, Field RW. Separation of long-range and short-range interactions in Rydberg states of diatomic molecules. J Chem Phys 2008; 128:194301. [DOI: 10.1063/1.2907858] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022] Open
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47
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Editorial: Christian Jungen. Mol Phys 2007. [DOI: 10.1080/00268970701524457] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Paul THA, Cruse HA, Wörner HJ, Merkt F. Structure and dynamics of the high gerade Rydberg states of D2 in the vicinity of the adiabatic ionization threshold. Mol Phys 2007. [DOI: 10.1080/00268970601146898] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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49
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Kovacev M, Fomichev SV, Priori E, Mairesse Y, Merdji H, Monchicourt P, Breger P, Norin J, Persson A, L'Huillier A, Wahlström CG, Carré B, Salières P. Extreme ultraviolet Fourier-transform spectroscopy with high order harmonics. PHYSICAL REVIEW LETTERS 2005; 95:223903. [PMID: 16384221 DOI: 10.1103/physrevlett.95.223903] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2005] [Indexed: 05/05/2023]
Abstract
We demonstrate a new scheme for extreme ultraviolet (xuv) Fourier-transform spectroscopy based on the generation of two phase-locked high-harmonic beams. It allows us to measure for the first time interferograms at wavelengths as short as 90 nm, and open the perspective of performing high-resolution Fourier-transform absorption spectroscopy in the xuv. Our measurements also demonstrate that a precise control of the relative phase of harmonic pulses can be obtained with an accuracy on an attosecond time scale, of importance for future xuv pump-xuv probe attosecond spectroscopy.
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Affiliation(s)
- M Kovacev
- CEA/DSM/DRECAM/SPAM, bât. 522, Centre d'Etudes de Saclay, 91191 Gif-sur-Yvette, France
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