1
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Amirtharaj S, Xie Z, Si Yu See J, Rolleri G, Malchow K, Chen W, Bouhelier A, Lörtscher E, Galland C. Light Emission and Conductance Fluctuations in Electrically Driven and Plasmonically Enhanced Molecular Junctions. ACS PHOTONICS 2024; 11:2388-2396. [PMID: 38911841 PMCID: PMC11191743 DOI: 10.1021/acsphotonics.4c00291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/15/2024] [Revised: 05/17/2024] [Accepted: 05/17/2024] [Indexed: 06/25/2024]
Abstract
Electrically connected and plasmonically enhanced molecular junctions combine the optical functionalities of high field confinement and enhancement (cavity function), and of high radiative efficiency (antenna function) with the electrical functionalities of molecular transport. Such combined optical and electrical probes have proven useful for the fundamental understanding of metal-molecule contacts and contribute to the development of nanoscale optoelectronic devices including ultrafast electronics and nanosensors. Here, we employ a self-assembled metal-molecule-metal junction with a nanoparticle bridge to investigate correlated fluctuations in conductance and tunneling-induced light emission at room temperature. Despite the presence of hundreds of molecules in the junction, the electrical conductance and light emission are both highly sensitive to atomic-scale fluctuations-a phenomenology reminiscent of picocavities observed in Raman scattering and of luminescence blinking from photoexcited plasmonic junctions. Discrete steps in conductance associated with fluctuating emission intensities through the multiple plasmonic modes of the junction are consistent with a finite number of randomly localized, point-like sources dominating the optoelectronic response. Contrasting with these microscopic fluctuations, the overall plasmonic and electronic functionalities of our devices feature long-term survival at room temperature and under an electrical bias of a few volts, allowing for measurements over several months.
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Affiliation(s)
- Sakthi
Priya Amirtharaj
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Zhiyuan Xie
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Josephine Si Yu See
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Gabriele Rolleri
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Konstantin Malchow
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Wen Chen
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Alexandre Bouhelier
- Laboratoire
Interdisciplinaire Carnot de Bourgogne CNRS UMR 6303, Université de Bourgogne, 21000 Dijon, France
| | - Emanuel Lörtscher
- IBM
Research Europe—Zurich, Säumerstrasse 4, CH-8803 Rüschlikon, Switzerland
| | - Christophe Galland
- Institute
of Physics, Ecole Polytechnique Fédérale
de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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2
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Wang Z, Zhou W, Yang M, Yang Y, Hu J, Qin C, Zhang G, Liu S, Chen R, Xiao L. The Geometry of Nanoparticle-on-Mirror Plasmonic Nanocavities Impacts Surface-Enhanced Raman Scattering Backgrounds. NANOMATERIALS (BASEL, SWITZERLAND) 2023; 14:53. [PMID: 38202508 PMCID: PMC10780556 DOI: 10.3390/nano14010053] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 12/21/2023] [Accepted: 12/21/2023] [Indexed: 01/12/2024]
Abstract
Surface-enhanced Raman scattering (SERS) has garnered substantial attention due to its ability to achieve single-molecule sensitivity by utilizing metallic nanostructures to amplify the exceedingly weak Raman scattering process. However, the introduction of metal nanostructures can induce a background continuum which can reduce the ultimate sensitivity of SERS in ways that are not yet well understood. Here, we investigate the impact of laser irradiation on both Raman scattering and backgrounds from self-assembled monolayers within nanoparticle-on-mirror plasmonic nanocavities with variable geometry. We find that laser irradiation can reduce the height of the monolayer by inducing an irreversible change in molecular conformation. The resulting increased plasmon confinement in the nanocavities not only enhances the SERS signal, but also provides momentum conservation in the inelastic light scattering of electrons, contributing to the enhancement of the background continuum. The plasmon confinement can be modified by changing the size and the geometry of nanoparticles, resulting in a nanoparticle geometry-dependent background continuum in SERS. Our work provides new routes for further modifying the geometry of plasmonic nanostructures to improve SERS sensitivity.
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Affiliation(s)
- Zixin Wang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Wenjin Zhou
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Min Yang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Yong Yang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Jianyong Hu
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Chengbing Qin
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Guofeng Zhang
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Shaoding Liu
- Key Laboratory of Advanced Transducers and Intelligence Control System, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China
| | - Ruiyun Chen
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
| | - Liantuan Xiao
- State Key Laboratory of Quantum Optics and Quantum Optics Devices, Institute of Laser Spectroscopy, Shanxi University, Taiyuan 030006, China
- Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China
- College of Physics, Taiyuan University of Technology, Taiyuan 030024, China
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3
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Chang L, Liu X, Lee CY, Zhang W. Nanorod reassembling on a sprayed SERS substrate under confined evaporation inducing ultrasensitive TPhT detection. Anal Chim Acta 2023; 1279:341825. [PMID: 37827623 DOI: 10.1016/j.aca.2023.341825] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 08/09/2023] [Accepted: 09/14/2023] [Indexed: 10/14/2023]
Abstract
Triphenyltin is an estrogen like pollutant that poses significant environmental threats due to its highly accumulative toxicity. To improve regulation, a fast and sensitive detection method is urgently needed. SERS can capture fingerprint information and is capable of trace detection, making it an ideal solution. Here, we present a sprayed substrate comprised of lightconfining structures and gold nanorod assemblies that are easy to prepare, low-cost, and can form dense hotspots under confined evaporation. The substrates are three-layered: initially, a gold nanorod layer is sprayed as a support, then sputter Ag film on the surface to form a lightconfining structure, followed by another gold nanorod layer sprayed on the Ag film. The coupling of nanorod assembly with lightconfining Ag films leads to 10-fold sensitivity. In addition, sample droplet evaporation in a limited area called confined evaporation contributes to nanorod migration and reassembly on the corner of the substrate, enhancing analytes absorption, and substantially lowered the detection limits. By systematically evaluating the substrate performance, we were able to obtain an average enhancement factor of 3.31 × 106. After confined evaporation, the detection limit reached 10-18 M for R6G and for triphenyltin, it achieved 10-9 M. This novel method represents a significant advancement toward SERS application in detecting trace pollutants.
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Affiliation(s)
- Lin Chang
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, PR China
| | - Xiaohong Liu
- National University of Singapore (Chongqing) Research Institute, Chongqing, 401123, PR China
| | - Chong-Yew Lee
- School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, 11800, Malaysia
| | - Wei Zhang
- Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, PR China; College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, 100049, PR China.
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4
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Yao L, Hao Q, Li M, Fan X, Li G, Tang X, Wei Y, Wang J, Qiu T. Flexible plasmonic nanocavities: a universal platform for the identification of molecular orientations. NANOSCALE 2023; 15:6588-6595. [PMID: 36961297 DOI: 10.1039/d3nr01059g] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
The molecular orientation provides fundamental images to understand molecular behaviors in chemistry. Herein, we propose and demonstrate sandwich plasmonic nanocavities as a surface-selection ruler to illustrate the molecular orientations by surface-enhanced Raman spectroscopy (SERS). The field vector in the plasmonic nanocavity presents a transverse spinning feature under specific excitations, allowing the facile modulation of the field polarizations to selectively amplify the Raman modes of the target molecules. It does not require the knowledge of the Raman spectrum of a bare molecule as a standard and thus can be extended as a universal ruler for the identification of molecular orientations. We investigated the most widely used Raman probe, Rhodamine 6G (R6G) on the Au surface and tried to clarify the arguments about its orientations from our perspectives. The experimental results suggest concentration-dependent adsorption configurations of R6G: it adsorbs on Au primarily via an ethylamine group with the xanthene ring lying flatly on the metal surface at low concentrations, and the molecular orientation gradually changes from "flat" to "upright" with the increase of molecular concentrations.
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Affiliation(s)
- Lei Yao
- School of physics, Southeast University, Nanjing 211189, P. R. China.
| | - Qi Hao
- School of physics, Southeast University, Nanjing 211189, P. R. China.
| | - Mingze Li
- School of physics, Southeast University, Nanjing 211189, P. R. China.
| | - Xingce Fan
- School of physics, Southeast University, Nanjing 211189, P. R. China.
| | - Guoqun Li
- School of physics, Southeast University, Nanjing 211189, P. R. China.
| | - Xiao Tang
- School of physics, Southeast University, Nanjing 211189, P. R. China.
| | - Yunjia Wei
- School of physics, Southeast University, Nanjing 211189, P. R. China.
| | - Jiawei Wang
- School of Electronic and Information Engineering, Harbin Institute of Technology (Shenzhen), Shenzhen 518055, China
| | - Teng Qiu
- School of physics, Southeast University, Nanjing 211189, P. R. China.
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5
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Shlesinger I, Palstra IM, Koenderink AF. Integrated Sideband-Resolved SERS with a Dimer on a Nanobeam Hybrid. PHYSICAL REVIEW LETTERS 2023; 130:016901. [PMID: 36669214 DOI: 10.1103/physrevlett.130.016901] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 12/14/2022] [Indexed: 06/17/2023]
Abstract
In analogy to cavity optomechanics, enhancing specific sidebands of a Raman process with narrowband optical resonators would allow for parametric amplification, entanglement of light and molecular vibrations, and reduced transduction noise. We report on the demonstration of waveguide-addressable sideband-resolved surface-enhanced Raman scattering (SERS). We realized a hybrid plasmonic-photonic resonator consisting of a 1D photonic crystal cavity decorated with a sub-20 nm gap dimer nanoantenna. Hybrid resonances in the near-IR provide designer Q factors of 1000, and Q/V=(λ^{3}/10^{6})^{-1}, with SERS signal strength on par with levels found in state-of-the-art purely plasmonic systems. We evidence Fano line shapes in the SERS enhancement of organic molecules, and quantitatively separate out the pump enhancement and optical reservoir contributions.
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Affiliation(s)
- Ilan Shlesinger
- Department of Physics of Information in Matter and Center for Nanophotonics, NWO-I Institute AMOLF, Science Park 104, NL1098XH Amsterdam, Netherlands
| | - Isabelle M Palstra
- Department of Physics of Information in Matter and Center for Nanophotonics, NWO-I Institute AMOLF, Science Park 104, NL1098XH Amsterdam, Netherlands
- Institute of Physics, University of Amsterdam, NL1098XH Amsterdam, Netherlands
| | - A Femius Koenderink
- Department of Physics of Information in Matter and Center for Nanophotonics, NWO-I Institute AMOLF, Science Park 104, NL1098XH Amsterdam, Netherlands
- Institute of Physics, University of Amsterdam, NL1098XH Amsterdam, Netherlands
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6
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Elliott E, Bedingfield K, Huang J, Hu S, de Nijs B, Demetriadou A, Baumberg JJ. Fingerprinting the Hidden Facets of Plasmonic Nanocavities. ACS PHOTONICS 2022; 9:2643-2651. [PMID: 35996364 PMCID: PMC9389613 DOI: 10.1021/acsphotonics.2c00116] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Indexed: 05/30/2023]
Abstract
The optical properties of nanogap plasmonic cavities formed by a NanoParticle-on-Mirror (NPoM, or patch antenna) are determined here, across a wide range of geometric parameters including the nanoparticle diameter, gap refractive index, gap thickness, facet size and shape. Full understanding of the confined optical modes allows these nanocavities to be utilized in a wide range of experiments across many fields. We show that the gap thickness t and refractive index n are spectroscopically indistinguishable, accounted for by a single gap parameter G = n/t 0.47. Simple tuning of mode resonant frequencies and strength is found for each quasi-normal mode, revealing a spectroscopic "fingerprint" for each facet shape, on both truncated spherical and rhombicuboctahedral nanoparticles. This is applied to determine the most likely nanoscale morphology of facets hidden below each NPoM in experiment, as well as to optimize the constructs for different applications. Simple scaling relations are demonstrated, and an online tool for general use is provided.
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Affiliation(s)
- Eoin Elliott
- NanoPhotonics
Centre, Cavendish Laboratory, University
of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Kalun Bedingfield
- School
of Physics and Astronomy, University of
Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Junyang Huang
- NanoPhotonics
Centre, Cavendish Laboratory, University
of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Shu Hu
- NanoPhotonics
Centre, Cavendish Laboratory, University
of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Bart de Nijs
- NanoPhotonics
Centre, Cavendish Laboratory, University
of Cambridge, Cambridge CB3 0HE, United Kingdom
| | - Angela Demetriadou
- School
of Physics and Astronomy, University of
Birmingham, Edgbaston, Birmingham, B15 2TT, United Kingdom
| | - Jeremy J Baumberg
- NanoPhotonics
Centre, Cavendish Laboratory, University
of Cambridge, Cambridge CB3 0HE, United Kingdom
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7
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Diehn S, Schlaad H, Kneipp J. Multivariate Imaging for Fast Evaluation of In Situ Dark Field Microscopy Hyperspectral Data. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27165146. [PMID: 36014387 PMCID: PMC9413337 DOI: 10.3390/molecules27165146] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/21/2022] [Revised: 08/09/2022] [Accepted: 08/10/2022] [Indexed: 11/20/2022]
Abstract
Dark field scattering microscopy can create large hyperspectral data sets that contain a wealth of information on the properties and the molecular environment of noble metal nanoparticles. For a quick screening of samples of microscopic dimensions that contain many different types of plasmonic nanostructures, we propose a multivariate analysis of data sets of thousands to several hundreds of thousands of scattering spectra. By using non-negative matrix factorization for decomposing the spectra, components are identified that represent individual plasmon resonances and relative contributions of these resonances to particular microscopic focal volumes in the mapping data sets. Using data from silver and gold nanoparticles in the presence of different molecules, including gold nanoparticle-protein agglomerates or silver nanoparticles forming aggregates in the presence of acrylamide, plasmonic properties are observed that differ from those of the original nanoparticles. For the case of acrylamide, we show that the plasmon resonances of the silver nanoparticles are ideally suited to support surface enhanced Raman scattering (SERS) and the two-photon excited process of surface enhanced hyper Raman scattering (SEHRS). Both vibrational tools give complementary information on the in situ formed polyacrylamide and the molecular composition at the nanoparticle surface.
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Affiliation(s)
- Sabrina Diehn
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany
| | - Helmut Schlaad
- Institute of Chemistry, University of Potsdam, Karl-Liebknecht-Str. 24-25, 14476 Potsdam, Germany
| | - Janina Kneipp
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany
- Correspondence: ; Tel.: +49-30-2093-82632
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8
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Koczor-Benda Z, Roelli P, Galland C, Rosta E. Molecular Vibration Explorer: an Online Database and Toolbox for Surface-Enhanced Frequency Conversion and Infrared and Raman Spectroscopy. J Phys Chem A 2022; 126:4657-4663. [PMID: 35792893 PMCID: PMC9310003 DOI: 10.1021/acs.jpca.2c03700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
![]()
We present Molecular
Vibration Explorer, a freely accessible online
database and interactive tool for exploring vibrational spectra and
tensorial light-vibration coupling strengths of a large collection
of thiolated molecules. The “Gold” version of the database
gathers the results from density functional theory calculations on
2800 commercially available thiol compounds linked to a gold atom,
with the main motivation to screen the best molecules for THz and
mid-infrared to visible upconversion. Additionally, the “Thiol”
version of the database contains results for 1900 unbound thiolated
compounds. They both provide access to a comprehensive set of computed
spectroscopic parameters for all vibrational modes of all molecules
in the database. The user can simultaneously investigate infrared
absorption, Raman scattering, and vibrational sum- and difference-frequency
generation cross sections. Molecules can be screened for various parameters
in custom frequency ranges, such as a large Raman cross-section under
a specific molecular orientation, or a large orientation-averaged
sum-frequency generation (SFG) efficiency. The user can select polarization
vectors for the electromagnetic fields, set the orientation of the
molecule, and customize parameters for plotting the corresponding
IR, Raman, and sum-frequency spectra. We illustrate the capabilities
of this tool with selected applications in the field of surface-enhanced
spectroscopy.
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Affiliation(s)
- Zsuzsanna Koczor-Benda
- Department of Physics and Astronomy, University College London, London, WC1E 6BT, United Kingdom.,Department of Chemistry, King's College London, London, SE1 1DB, United Kingdom
| | - Philippe Roelli
- Nano-Optics Group, CIC nanoGUNE BRTA, 20018 San Sebastián, Spain
| | - Christophe Galland
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Edina Rosta
- Department of Physics and Astronomy, University College London, London, WC1E 6BT, United Kingdom.,Department of Chemistry, King's College London, London, SE1 1DB, United Kingdom
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9
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Vázquez-Lozano JE, Baumberg JJ, Martínez A. Enhanced excitation and readout of plasmonic cavity modes in NPoM via SiN waveguides for on-chip SERS. OPTICS EXPRESS 2022; 30:4553-4563. [PMID: 35209689 DOI: 10.1364/oe.446895] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/27/2021] [Accepted: 12/27/2021] [Indexed: 06/14/2023]
Abstract
Metallic nanoparticle-on-a-mirror (NPoM) cavities enable extreme field confinement in sub-nm gaps, leading to unrivaled performance for nonlinear processes such as surface-enhanced Raman scattering (SERS). So far, prevailing experimental approaches based on NPoMs have been performed by means of free-space light excitation and collection under oblique incidence, since the fundamental radiatively-coupled NPoM mode does not scatter in the normal direction. Retaining this working principle, here we numerically show that plasmonic cavity modes in NPoM configurations can be efficiently excited in an integrated SERS approach through TM guided modes of silicon nitride (SiN) waveguides. Intensity enhancements beyond 105 can be achieved for gap spacings around 1 nm. So as to reduce unwanted SiN Raman background, the output Stokes signals are transferred to transversely placed waveguides, reaching coupling efficiencies of up to 10%. Geometrical parameters such as the gap thickness as well as the radius and position of the nanoparticle provide full control over the main spectral features, thereby enabling us to engineer and drive the optical response of NPoMs for high-performance SERS in Si-based photonic integrated platforms.
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10
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Schörner C, Lippitz M. High-Q plasmonic nanowire-on-mirror resonators by atomically smooth single-crystalline silver flakes. J Chem Phys 2021; 155:234202. [PMID: 34937368 DOI: 10.1063/5.0074387] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Plasmonic nanoparticles in close vicinity to a metal surface confine light to nanoscale volumes within the insulating gap. With gap sizes in the range of a few nanometers or below, atomic-scale dynamical phenomena within the nanogap come into reach. However, at these tiny scales, an ultra-smooth material is a crucial requirement. Here, we demonstrate large-scale (50 μm) single-crystalline silver flakes with a truly atomically smooth surface, which are an ideal platform for vertically assembled silver plasmonic nanoresonators. We investigate crystalline silver nanowires in a sub-2 nm separation to the silver surface and observe narrow plasmonic resonances with a quality factor Q of about 20. We propose a concept toward the observation of the spectral diffusion of the lowest-frequency cavity plasmon resonance and present first measurements. Our study demonstrates the benefit of using purely crystalline silver for plasmonic nanoparticle-on-mirror resonators and further paves the way toward the observation of dynamic phenomena within a nanoscale gap.
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Affiliation(s)
| | - Markus Lippitz
- Experimental Physics III, University of Bayreuth, Bayreuth, Germany
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11
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Chen W, Roelli P, Hu H, Verlekar S, Amirtharaj SP, Barreda AI, Kippenberg TJ, Kovylina M, Verhagen E, Martínez A, Galland C. Continuous-wave frequency upconversion with a molecular optomechanical nanocavity. Science 2021; 374:1264-1267. [PMID: 34855500 DOI: 10.1126/science.abk3106] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Wen Chen
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Philippe Roelli
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Huatian Hu
- Hubei Key Laboratory of Optical Information and Pattern Recognition, Wuhan Institute of Technology, Wuhan 430205, China
| | - Sachin Verlekar
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Sakthi Priya Amirtharaj
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Angela I Barreda
- Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, 07745 Jena, Germany
| | - Tobias J Kippenberg
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - Miroslavna Kovylina
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Ewold Verhagen
- Center for Nanophotonics, AMOLF, 1098 XG Amsterdam, Netherlands
| | - Alejandro Martínez
- Nanophotonics Technology Center, Universitat Politècnica de València, 46022 Valencia, Spain
| | - Christophe Galland
- Institute of Physics, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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