1
|
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.
Collapse
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
| |
Collapse
|
2
|
Wang Z, Kalathingal V, Trushin M, Liu J, Wang J, Guo Y, Özyilmaz B, Nijhuis CA, Eda G. Upconversion electroluminescence in 2D semiconductors integrated with plasmonic tunnel junctions. NATURE NANOTECHNOLOGY 2024:10.1038/s41565-024-01650-0. [PMID: 38641642 DOI: 10.1038/s41565-024-01650-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2023] [Accepted: 03/13/2024] [Indexed: 04/21/2024]
Abstract
Plasmonic tunnel junctions are a unique electroluminescent system in which light emission occurs via an interplay between tunnelling electrons and plasmonic fields instead of electron-hole recombination as in conventional light-emitting diodes. It was previously shown that placing luminescent molecules in the tunneling pathway of nanoscopic tunnel junctions results in peculiar upconversion electroluminescence where the energy of emitted photons exceeds that of excitation electrons. Here we report the observation of upconversion electroluminescence in macroscopic van der Waals plasmonic tunnel junctions comprising gold and few-layer graphene electrodes separated by a ~2-nm-thick hexagonal boron nitride tunnel barrier and a monolayer semiconductor. We find that the semiconductor ground exciton emission is triggered at excitation electron energies lower than the semiconductor optical gap. Interestingly, this upconversion is reached in devices operating at a low conductance (<10-6 S) and low power density regime (<102 W cm-2), defying explanation through existing proposed mechanisms. By examining the scaling relationship between plasmonic and excitonic emission intensities, we elucidate the role of inelastic electron tunnelling dipoles that induce optically forbidden transitions in the few-layer graphene electrode and ultrafast hot carrier transfer across the van der Waals interface.
Collapse
Affiliation(s)
- Zhe Wang
- Department of Chemistry, National University of Singapore, Singapore, Singapore
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Vijith Kalathingal
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
- Department of Physics, Kannur University, Swami Anandatheertha Campus-Payyanur, Kannur, India
| | - Maxim Trushin
- Institute for Functional Intelligent Materials, National University of Singapore, Singapore, Singapore
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore, Singapore
- Department of Material Science and Engineering, National University of Singapore, Singapore, Singapore
| | - Jiawei Liu
- Institute for Functional Intelligent Materials, National University of Singapore, Singapore, Singapore
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore, Singapore
- Department of Physics, National University of Singapore, Singapore, Singapore
| | - Junyong Wang
- CAS Key Laboratory of Nano-Bio Interface and Key Laboratory of Nanodevices and Applications, i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou, China
| | - Yongxin Guo
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore, Singapore
| | - Barbaros Özyilmaz
- Institute for Functional Intelligent Materials, National University of Singapore, Singapore, Singapore
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore, Singapore
- Department of Material Science and Engineering, National University of Singapore, Singapore, Singapore
- Department of Physics, National University of Singapore, Singapore, Singapore
| | - Christian A Nijhuis
- Hybrid Materials for Opto-Electronics Group, Department of Molecules and Materials, MESA+ Institute for Nanotechnology, Molecules Center and Center for Brain-Inspired Nano Systems, Faculty of Science and Technology, University of Twente, Enschede, the Netherlands.
| | - Goki Eda
- Department of Chemistry, National University of Singapore, Singapore, Singapore.
- Centre for Advanced 2D Materials and Graphene Research Centre, National University of Singapore, Singapore, Singapore.
- Department of Physics, National University of Singapore, Singapore, Singapore.
| |
Collapse
|
3
|
Luo Y, Kong FF, Tian XJ, Yu YJ, Jing SH, Zhang C, Chen G, Zhang Y, Zhang Y, Li XG, Zhang ZY, Dong ZC. Anomalously bright single-molecule upconversion electroluminescence. Nat Commun 2024; 15:1677. [PMID: 38395971 PMCID: PMC10891098 DOI: 10.1038/s41467-024-45450-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2023] [Accepted: 01/23/2024] [Indexed: 02/25/2024] Open
Abstract
Efficient upconversion electroluminescence is highly desirable for a broad range of optoelectronic applications, yet to date, it has been reported only for ensemble systems, while the upconversion electroluminescence efficiency remains very low for single-molecule emitters. Here we report on the observation of anomalously bright single-molecule upconversion electroluminescence, with emission efficiencies improved by more than one order of magnitude over previous studies, and even stronger than normal-bias electroluminescence. Intuitively, the improvement is achieved via engineering the energy-level alignments at the molecule-substrate interface so as to activate an efficient spin-triplet mediated upconversion electroluminescence mechanism that only involves pure carrier injection steps. We further validate the intuitive picture with the construction of delicate electroluminescence diagrams for the excitation of single-molecule electroluminescence, allowing to readily identify the prerequisite conditions for producing efficient upconversion electroluminescence. These findings provide deep insights into the microscopic mechanism of single-molecule upconversion electroluminescence and organic electroluminescence in general.
Collapse
Affiliation(s)
- Yang Luo
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Fan-Fang Kong
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Xiao-Jun Tian
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Yun-Jie Yu
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Shi-Hao Jing
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Chao Zhang
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
| | - Gong Chen
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China.
| | - Yang Zhang
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
- School of Physics and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, 230088, China
| | - Yao Zhang
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
- School of Physics and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, 230088, China
| | - Xiao-Guang Li
- Institute for Advanced Study, Shenzhen University, Shenzhen, 518060, China
| | - Zhen-Yu Zhang
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
- School of Physics and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China
- Hefei National Laboratory, University of Science and Technology of China, Hefei, 230088, China
| | - Zhen-Chao Dong
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Research Center for Physical Sciences at the Microscale and CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China.
- School of Physics and Department of Chemical Physics, University of Science and Technology of China, Hefei, Anhui, 230026, China.
- Hefei National Laboratory, University of Science and Technology of China, Hefei, 230088, China.
| |
Collapse
|
4
|
Zhu Y, Yang J, Abad-Arredondo J, Fernández-Domínguez AI, Garcia-Vidal FJ, Natelson D. Electroluminescence as a Probe of Strong Exciton-Plasmon Coupling in Few-Layer WSe 2. NANO LETTERS 2024; 24:525-532. [PMID: 38109687 DOI: 10.1021/acs.nanolett.3c04684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/20/2023]
Abstract
The manipulation of coupled quantum excitations is of fundamental importance in realizing novel photonic and optoelectronic devices. We use electroluminescence to probe plasmon-exciton coupling in hybrid structures consisting of a nanoscale plasmonic tunnel junction and few-layer two-dimensional transition-metal dichalcogenide transferred onto the junction. The resulting hybrid states act as a novel dielectric environment that affects the radiative recombination of hot carriers in the plasmonic nanostructure. We determine the plexcitonic spectrum from the electroluminescence and find Rabi splittings exceeding 50 meV in the strong coupling regime. Our experimental findings are supported by electromagnetic simulations that enable us to explore systematically and in detail the emergence of plexciton polaritons as well as the polarization characteristics of their far-field emission. Electroluminescence modulated by plexciton coupling provides potential applications for engineering compact photonic devices with tunable optical and electrical properties.
Collapse
Affiliation(s)
- Yunxuan Zhu
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Jiawei Yang
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Jaime Abad-Arredondo
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Antonio I Fernández-Domínguez
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Francisco J Garcia-Vidal
- Departamento de Física Teórica de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, E-28049 Madrid, Spain
| | - Douglas Natelson
- Department of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| |
Collapse
|
5
|
Shan S, Huang J, Papadopoulos S, Khelifa R, Taniguchi T, Watanabe K, Wang L, Novotny L. Overbias Photon Emission from Light-Emitting Devices Based on Monolayer Transition Metal Dichalcogenides. NANO LETTERS 2023; 23:10908-10913. [PMID: 38048755 PMCID: PMC10722526 DOI: 10.1021/acs.nanolett.3c03155] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2023] [Revised: 11/24/2023] [Accepted: 11/28/2023] [Indexed: 12/06/2023]
Abstract
Tunneling light-emitting devices (LEDs) based on transition metal dichalcogenides (TMDs) and other two-dimensional (2D) materials are a new platform for on-chip optoelectronic integration. Some of the physical processes underlying this LED architecture are not fully understood, especially the emission at photon energies higher than the applied electrostatic potential, so-called overbias emission. Here we report overbias emission for potentials that are near half of the optical bandgap energy in TMD-based tunneling LEDs. We show that this emission is not thermal in nature but consistent with exciton generation via a two-electron coherent tunneling process.
Collapse
Affiliation(s)
- Shengyu Shan
- Photonics
Laboratory, ETH Zürich, 8093 Zürich, Switzerland
| | - Jing Huang
- Photonics
Laboratory, ETH Zürich, 8093 Zürich, Switzerland
| | | | - Ronja Khelifa
- Photonics
Laboratory, ETH Zürich, 8093 Zürich, Switzerland
| | - Takashi Taniguchi
- International
Center for Materials Nanoarchitectonics, National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Kenji Watanabe
- Research
Center for Functional Materials, National
Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Lujun Wang
- Photonics
Laboratory, ETH Zürich, 8093 Zürich, Switzerland
| | - Lukas Novotny
- Photonics
Laboratory, ETH Zürich, 8093 Zürich, Switzerland
| |
Collapse
|
6
|
Erez-Cohen O, Brontvein O, Bar-Joseph I. Electrically Driven Plasmons in Metal-Insulator-Semiconductor Tunnel Junctions: The Role of Silicon Amorphization. NANO LETTERS 2023; 23:2233-2238. [PMID: 36856602 PMCID: PMC10037326 DOI: 10.1021/acs.nanolett.2c04863] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/12/2022] [Revised: 02/25/2023] [Indexed: 06/18/2023]
Abstract
We investigate electrically driven plasmon (EDP) emission in metal-insulator-semiconductor tunnel junctions. We find that amorphization of the silicon crystal at a narrow region near the junction due to the applied voltage plays a critical role in determining the nature of the emission. Furthermore, we suggest that the change in the properties of the insulating layer above a threshold voltage determines the EDP spatial properties, from being spatially uniform when the device is subjected to low voltages, to a spotty pattern peaking at high voltages. We emphasize the role of the high-energy emission as an unambiguous tool for distinguishing between EDP and radiative recombination of electrons and holes in the semiconductor.
Collapse
Affiliation(s)
- Omer Erez-Cohen
- Department
of Condensed Matter Physics, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Olga Brontvein
- Department
of Chemical Research Support, Weizmann Institute
of Science, Rehovot 7610001, Israel
| | - Israel Bar-Joseph
- Department
of Condensed Matter Physics, Weizmann Institute
of Science, Rehovot 7610001, Israel
| |
Collapse
|
7
|
Zhu Y, Cui L, Abbasi M, Natelson D. Tuning Light Emission Crossovers in Atomic-Scale Aluminum Plasmonic Tunnel Junctions. NANO LETTERS 2022; 22:8068-8075. [PMID: 36197739 DOI: 10.1021/acs.nanolett.2c02013] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Atomic-sized plasmonic tunnel junctions are of fundamental interest, with great promise as the smallest on-chip light sources in various optoelectronic applications. Several mechanisms of light emission in electrically driven plasmonic tunnel junctions have been proposed, from single-electron or higher-order multielectron inelastic tunneling to recombination from a steady-state population of hot carriers. By progressively altering the tunneling conductance of an aluminum junction, we tune the dominant light emission mechanism through these possibilities for the first time, finding quantitative agreement with theory in each regime. Improved plasmonic resonances in the energy range of interest increase photon yields by 2 orders of magnitude. These results demonstrate that the dominant emission mechanism is set by a combination of tunneling rate, hot carrier relaxation time scales, and junction plasmonic properties.
Collapse
Affiliation(s)
- Yunxuan Zhu
- Department of Physics and Astronomy, Rice University, Houston, Texas77005, United States
| | - Longji Cui
- Paul M. Rady Department of Mechanical Engineering, University of Colorado, Boulder, Colorado80309, United States
- Materials Science and Engineering Program, University of Colorado, Boulder, Colorado80309, United States
| | - Mahdiyeh Abbasi
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas77005, United States
| | - Douglas Natelson
- Department of Physics and Astronomy, Rice University, Houston, Texas77005, United States
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas77005, United States
- Department of Materials Science and Nanoengineering, Rice University, Houston, Texas77005, United States
| |
Collapse
|
8
|
Rosławska A, Merino P, Grewal A, Leon CC, Kuhnke K, Kern K. Atomic-Scale Structural Fluctuations of a Plasmonic Cavity. NANO LETTERS 2021; 21:7221-7227. [PMID: 34428071 PMCID: PMC8887667 DOI: 10.1021/acs.nanolett.1c02207] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Optical spectromicroscopies, which can reach atomic resolution due to plasmonic enhancement, are perturbed by spontaneous intensity modifications. Here, we study such fluctuations in plasmonic electroluminescence at the single-atom limit profiting from the precision of a low-temperature scanning tunneling microscope. First, we investigate the influence of a controlled single-atom transfer from the tip to the sample on the plasmonic properties of the junction. Next, we form a well-defined atomic contact of several quanta of conductance. In contact, we observe changes of the electroluminescence intensity that can be assigned to spontaneous modifications of electronic conductance, plasmonic excitation, and optical antenna properties all originating from minute atomic rearrangements at or near the contact. Our observations are relevant for the understanding of processes leading to spontaneous intensity variations in plasmon-enhanced atomic-scale spectroscopies such as intensity blinking in picocavities.
Collapse
Affiliation(s)
- Anna Rosławska
- Max-Planck-Institut
für Festkörperforschung, D-70569 Stuttgart, Germany
- Université
de Strasbourg, CNRS, IPCMS, UMR 7504, F-67000 Strasbourg, France
| | - Pablo Merino
- Max-Planck-Institut
für Festkörperforschung, D-70569 Stuttgart, Germany
- Instituto
de Ciencia de Materiales de Madrid, CSIC, E-28049 Madrid, Spain
- Instituto
de Física Fundamental, CSIC, E-28006 Madrid, Spain
| | - Abhishek Grewal
- Max-Planck-Institut
für Festkörperforschung, D-70569 Stuttgart, Germany
| | | | - Klaus Kuhnke
- Max-Planck-Institut
für Festkörperforschung, D-70569 Stuttgart, Germany
| | - Klaus Kern
- Max-Planck-Institut
für Festkörperforschung, D-70569 Stuttgart, Germany
- Institut
de Physique, École Polytechnique
Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| |
Collapse
|
9
|
Martín-Jiménez A, Lauwaet K, Jover Ó, Granados D, Arnau A, Silkin VM, Miranda R, Otero R. Electronic Temperature and Two-Electron Processes in Overbias Plasmonic Emission from Tunnel Junctions. NANO LETTERS 2021; 21:7086-7092. [PMID: 34152778 DOI: 10.1021/acs.nanolett.1c00951] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
The accurate determination of electronic temperatures in metallic nanostructures is essential for many technological applications, like plasmon-enhanced catalysis or lithographic nanofabrication procedures. In this Letter, we demonstrate that the electronic temperature can be accurately measured by the shape of the tunnel electroluminescence emission edge in tunnel plasmonic nanocavities, which follows a universal thermal distribution with the bias voltage as the chemical potential of the photon population. A significant deviation between electronic and lattice temperatures is found below 30 K for tunnel currents larger than 15 nA. This deviation is rationalized as the result of a two-electron process in which the second electron excites plasmon modes with an energy distribution that reflects the higher temperature following the first tunneling event. These results dispel a long-standing controversy on the nature of overbias emission in tunnel junctions and adds a new method for the determination of electronic temperatures and quasiparticle dynamics.
Collapse
Affiliation(s)
| | | | - Óscar Jover
- IMDEA Nanoscience, 28049 Madrid, Spain
- Depto. de Física de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | | | - Andrés Arnau
- Donostia International Physics Center (DIPC), 20018 San Sebastián/Donostia, Spain
- Depto. de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Facultad de Química, Universidad del País Vasco UPV/EHU, Apartado 1072, 20080 San Sebastián/Donostia, Spain
- Centro de Fisica de Materiales CFM/MPC (CSIC-UPV/EHU), Paseo de Manuel Lardizabal 5, 20018 San Sebastián/Donostia, Spain
| | - Vyacheslav M Silkin
- Donostia International Physics Center (DIPC), 20018 San Sebastián/Donostia, Spain
- Depto. de Polímeros y Materiales Avanzados: Física, Química y Tecnología, Facultad de Química, Universidad del País Vasco UPV/EHU, Apartado 1072, 20080 San Sebastián/Donostia, Spain
- IKERBASQUE, Basque Foundation for Science, 48009 Bilbao, Spain
| | - Rodolfo Miranda
- IMDEA Nanoscience, 28049 Madrid, Spain
- Depto. de Física de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - Roberto Otero
- IMDEA Nanoscience, 28049 Madrid, Spain
- Depto. de Física de la Materia Condensada and Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| |
Collapse
|
10
|
Cui L, Zhu Y, Nordlander P, Di Ventra M, Natelson D. Thousand-fold Increase in Plasmonic Light Emission via Combined Electronic and Optical Excitations. NANO LETTERS 2021; 21:2658-2665. [PMID: 33710898 DOI: 10.1021/acs.nanolett.1c00503] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Surface plasmon enhanced processes and hot-carrier dynamics in plasmonic nanostructures are of great fundamental interest to reveal light-matter interactions at the nanoscale. Using plasmonic tunnel junctions as a platform supporting both electrically and optically excited localized surface plasmons, we report a much greater (over 1000× ) plasmonic light emission at upconverted photon energies under combined electro-optical excitation, compared with electrical or optical excitation separately. Two mechanisms compatible with the form of the observed spectra are interactions of plasmon-induced hot carriers and electronic anti-Stokes Raman scattering. Our measurement results are in excellent agreement with a theoretical model combining electro-optical generation of hot carriers through nonradiative plasmon excitation and hot-carrier relaxation. We also discuss the challenge of distinguishing relative contributions of hot carrier emission and the anti-Stokes electronic Raman process. This observed increase in above-threshold emission in plasmonic systems may open avenues in on-chip nanophotonic switching and hot-carrier photocatalysis.
Collapse
Affiliation(s)
- Longji Cui
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
- Paul M. Rady Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309, United States
- Materials Science and Engineering Program, University of Colorado, Boulder, Colorado 80309, United States
| | - Yunxuan Zhu
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
| | - Peter Nordlander
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, United States
- Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, United States
| | - Massimiliano Di Ventra
- Department of Physics, University of California San Diego, La Jolla, California 92093, United States
| | - Douglas Natelson
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, United States
- Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, United States
| |
Collapse
|
11
|
Shalem G, Erez-Cohen O, Mahalu D, Bar-Joseph I. Light Emission in Metal-Semiconductor Tunnel Junctions: Direct Evidence for Electron Heating by Plasmon Decay. NANO LETTERS 2021; 21:1282-1287. [PMID: 33497237 PMCID: PMC7883388 DOI: 10.1021/acs.nanolett.0c03945] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 01/14/2021] [Indexed: 05/26/2023]
Abstract
We study metal-insulator-semiconductor tunnel junctions where the metal electrode is a patterned gold layer, the insulator is a thin layer of Al2O3, and the semiconductor is p-type silicon. We observe light emission due to plasmon-assisted inelastic tunneling from the metal to the silicon valence band. The emission cutoff shifts to higher energies with increasing voltage, a clear signature of electrically driven plasmons. The cutoff energy exceeds the applied voltage, and a large fraction of the emission is above the threshold, ℏω > eV. We find that the emission spectrum manifests the Fermi-Dirac distribution of the electrons in the gold electrode. This distribution can be used to determine the effective electron temperature, Te, which is shown to have a linear dependence on the applied voltage. The strong correlation of Te with the plasmon energy serves as evidence that the mechanism for heating the electrons is plasmon decay at the source metal electrode.
Collapse
Affiliation(s)
- Guy Shalem
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Omer Erez-Cohen
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Diana Mahalu
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 7610001, Israel
| | - Israel Bar-Joseph
- Department of Condensed Matter Physics, Weizmann Institute of Science, Rehovot 7610001, Israel
| |
Collapse
|
12
|
Lebedev DV, Shkoldin VA, Mozharov AM, Permyakov DV, Dvoretckaia LN, Bogdanov AA, Samusev AK, Golubok AO, Mukhin IS. Scanning Tunneling Microscopy-Induced Light Emission and I( V) Study of Optical Near-Field Properties of Single Plasmonic Nanoantennas. J Phys Chem Lett 2021; 12:501-507. [PMID: 33373245 DOI: 10.1021/acs.jpclett.0c03039] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Electrically driven plasmonic nanoantennas can be integrated as a local source of the optical signal of advanced photonic schemes for on-chip data processing. The inelastic electron tunneling provides the photon generation or launch of surface plasmon waves. This process can be enhanced by the local density of optical states of nanoantennas. In this paper, we used scanning tunnel microscopy-induced light emission to probe the local optoelectronic properties of single gold nanodiscs. The electromagnetic field distribution in the vicinity of plasmonic structures was investigated with high spatial resolution. The obtained photon maps reveal the nonuniform distribution of electromagnetic near-fields, which is consistent with nanoantenna optical modes. Also, the analysis of derived I(V) curves showed a direct correlation between the nanoantenna optical states and the appearance of features on current-voltage characteristics.
Collapse
Affiliation(s)
- Denis V Lebedev
- Saint Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg 199034, Russia
- Institute for Analytical Instrumentation RAS, 26 Rizhskii pr., St. Petersburg 190103, Russia
- St. Petersburg Academic University, 8/3 Khlopina str., St. Petersburg 194021, Russia
| | - Vitaliy A Shkoldin
- St. Petersburg Academic University, 8/3 Khlopina str., St. Petersburg 194021, Russia
- ITMO University, 9 Kronverksky pr., St. Petersburg 197101, Russia
| | - Alexey M Mozharov
- St. Petersburg Academic University, 8/3 Khlopina str., St. Petersburg 194021, Russia
| | | | - Lilia N Dvoretckaia
- St. Petersburg Academic University, 8/3 Khlopina str., St. Petersburg 194021, Russia
| | | | - Anton K Samusev
- ITMO University, 9 Kronverksky pr., St. Petersburg 197101, Russia
| | - Alexander O Golubok
- Institute for Analytical Instrumentation RAS, 26 Rizhskii pr., St. Petersburg 190103, Russia
| | - Ivan S Mukhin
- St. Petersburg Academic University, 8/3 Khlopina str., St. Petersburg 194021, Russia
- ITMO University, 9 Kronverksky pr., St. Petersburg 197101, Russia
| |
Collapse
|
13
|
Fung ED, Venkataraman L. Too Cool for Blackbody Radiation: Overbias Photon Emission in Ambient STM Due to Multielectron Processes. NANO LETTERS 2020; 20:8912-8918. [PMID: 33206534 DOI: 10.1021/acs.nanolett.0c03994] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Light emission from tunnel junctions are a potential photon source for nanophotonic applications. Surprisingly, the photons emitted can have energies exceeding the energy supplied to the electrons by the bias. Three mechanisms for generating these so-called overbias photons have been proposed, but the relationship between these mechanisms has not been clarified. In this work, we argue that multielectron processes provide the best framework for understanding overbias light emission in tunnel junctions. Experimentally, we demonstrate for the first time that the superlinear dependence of emission on conductance predicted by this theory is robust to the temperature of the tunnel junction, indicating that tunnel junctions are a promising candidate for electrically driven broadband photon sources.
Collapse
Affiliation(s)
- E-Dean Fung
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
| | - Latha Venkataraman
- Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027, United States
- Department of Chemistry, Columbia University, New York, New York 10027, United States
| |
Collapse
|
14
|
Cui L, Zhu Y, Abbasi M, Ahmadivand A, Gerislioglu B, Nordlander P, Natelson D. Electrically Driven Hot-Carrier Generation and Above-Threshold Light Emission in Plasmonic Tunnel Junctions. NANO LETTERS 2020; 20:6067-6075. [PMID: 32568541 DOI: 10.1021/acs.nanolett.0c02121] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Above-threshold light emission from plasmonic tunnel junctions, when emitted photons have energies significantly higher than the energy scale of incident electrons, has attracted much recent interest in nano-optics, while the underlying physics remains elusive. We examine above-threshold light emission in electromigrated tunnel junctions. Our measurements over a large ensemble of devices demonstrate a giant (∼104) material-dependent photon yield (emitted photons per incident electrons). This dramatic effect cannot be explained only by the radiative field enhancement due to localized plasmons in the tunneling gap. Emission is well described by a Boltzmann spectrum with an effective temperature exceeding 2000 K, coupled to a plasmon-modified photonic density of states. The effective temperature is approximately linear in the applied bias, consistent with a suggested theoretical model describing hot-carrier dynamics driven by nonradiative decay of electrically excited localized plasmons. Electrically generated hot carriers and nontraditional light emission could open avenues for active photochemistry, optoelectronics, and quantum optics.
Collapse
Affiliation(s)
- Longji Cui
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
- Department of Mechanical Engineering, University of Colorado, Boulder, Colorado 80309, United States
- Materials Science and Engineering Program, University of Colorado, Boulder, Colorado 80309, United States
| | - Yunxuan Zhu
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
| | - Mahdiyeh Abbasi
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, United States
| | - Arash Ahmadivand
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, United States
| | - Burak Gerislioglu
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
| | - Peter Nordlander
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, United States
- Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, United States
| | - Douglas Natelson
- Department of Physics and Astronomy and Smalley-Curl Institute, Rice University, Houston, Texas 77005, United States
- Department of Electrical and Computer Engineering, Rice University, Houston, Texas 77005, United States
- Department of Materials Science and Nanoengineering, Rice University, Houston, Texas 77005, United States
| |
Collapse
|
15
|
Svatek SA, Kerfoot J, Summerfield A, Nizovtsev AS, Korolkov VV, Taniguchi T, Watanabe K, Antolín E, Besley E, Beton PH. Triplet Excitation and Electroluminescence from a Supramolecular Monolayer Embedded in a Boron Nitride Tunnel Barrier. NANO LETTERS 2020; 20:278-283. [PMID: 31821763 DOI: 10.1021/acs.nanolett.9b03787] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We show that ordered monolayers of organic molecules stabilized by hydrogen bonding on the surface of exfoliated few-layer hexagonal boron nitride (hBN) flakes may be incorporated into van der Waals heterostructures with integral few-layer graphene contacts forming a molecular/two-dimensional hybrid tunneling diode. Electrons can tunnel through the hBN/molecular barrier under an applied voltage VSD, and we observe molecular electroluminescence from an excited singlet state with an emitted photon energy hν > eVSD, indicating upconversion by energies up to ∼1 eV. We show that tunneling electrons excite embedded molecules into singlet states in a two-step process via an intermediate triplet state through inelastic scattering and also observe direct emission from the triplet state. These heterostructures provide a solid-state device in which spin-triplet states, which cannot be generated by optical transitions, can be controllably excited and provide a new route to investigate the physics, chemistry, and quantum spin-based applications of triplet generation, emission, and molecular photon upconversion.
Collapse
Affiliation(s)
| | | | | | - Anton S Nizovtsev
- Nikolaev Institute of Inorganic Chemistry , Siberian Branch of the Russian Academy of Sciences , Academician Lavrentiev Avenue 3 , Novosibirsk 630090 , Russian Federation
| | | | - Takashi Taniguchi
- National Institute for Materials Science , 1-1 Namiki , Tsukuba 305-0044 , Ibaraki , Japan
| | - Kenji Watanabe
- National Institute for Materials Science , 1-1 Namiki , Tsukuba 305-0044 , Ibaraki , Japan
| | - Elisa Antolín
- Instituto de Energía Solar , Universidad Politécnica de Madrid , Avenida Complutense 30 , Madrid 28040 , Spain
| | | | | |
Collapse
|
16
|
Parzefall M, Novotny L. Optical antennas driven by quantum tunneling: a key issues review. REPORTS ON PROGRESS IN PHYSICS. PHYSICAL SOCIETY (GREAT BRITAIN) 2019; 82:112401. [PMID: 31491785 DOI: 10.1088/1361-6633/ab4239] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/13/2023]
Abstract
Analogous to radio- and microwave antennas, optical nanoantennas are devices that receive and emit radiation at optical frequencies. Until recently, the realization of electrically driven optical antennas was an outstanding challenge in nanophotonics. In this review we discuss and analyze recent reports in which quantum tunneling-specifically inelastic electron tunneling-is harnessed as a means to convert electrical energy into photons, mediated by optical antennas. To aid this analysis we introduce the fundamentals of optical antennas and inelastic electron tunneling. Our discussion is focused on recent progress in the field and on future directions and opportunities.
Collapse
|
17
|
Chen G, Luo Y, Gao H, Jiang J, Yu Y, Zhang L, Zhang Y, Li X, Zhang Z, Dong Z. Spin-Triplet-Mediated Up-Conversion and Crossover Behavior in Single-Molecule Electroluminescence. PHYSICAL REVIEW LETTERS 2019; 122:177401. [PMID: 31107062 DOI: 10.1103/physrevlett.122.177401] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Revised: 02/22/2019] [Indexed: 05/24/2023]
Abstract
Scanning-tunneling-microscope-induced light emission serves as a powerful approach in revealing and manipulating the optical properties of molecular species, intermolecular energy transfer, and plasmon-molecule coupling. Earlier studies have established the existence of molecular up-conversion electroluminescence in diverse situations, but the underlying microscopic mechanisms are still under active debate, dominated by intermolecular triplet-triplet annihilation and plasmonic pumping. Here we report on the experimental realization of up-conversion electroluminescence from a prototypical single phthalocyanine molecule, allowing us to unambiguously rule out mechanisms based on intermolecular coupling and also offering unprecedented opportunities to elucidate much richer characteristics unforeseen in previous studies. In particular, the bias-dependent emission intensity displays three distinct regions with different nonlinear current dependences, which can be attributed to crossover behavior caused by the interplay between inelastic electron scattering and carrier-injection processes. We also develop a microscopic description to capture the essential physics involved in up-conversion electroluminescence mediated by a proper intermediate spin-triplet state.
Collapse
Affiliation(s)
- Gong Chen
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
- School of Physics and Engineering, Zhengzhou University, Zhengzhou, Henan 450052, China
| | - Yang Luo
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Hongying Gao
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Jun Jiang
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yunjie Yu
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Li Zhang
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Yang Zhang
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Xiaoguang Li
- Institute for Advanced Study, Shenzhen University, Shenzhen 518060, China
| | - Zhenyu Zhang
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| | - Zhenchao Dong
- International Center for Quantum Design of Functional Materials (ICQD), Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, China
| |
Collapse
|
18
|
Leon CC, Rosławska A, Grewal A, Gunnarsson O, Kuhnke K, Kern K. Photon superbunching from a generic tunnel junction. SCIENCE ADVANCES 2019; 5:eaav4986. [PMID: 31093525 PMCID: PMC6510551 DOI: 10.1126/sciadv.aav4986] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Accepted: 03/26/2019] [Indexed: 05/21/2023]
Abstract
Generating time-correlated photon pairs at the nanoscale is a prerequisite to creating highly integrated optoelectronic circuits that perform quantum computing tasks based on heralded single photons. Here, we demonstrate fulfilling this requirement with a generic tip-surface metal junction. When the junction is luminescing under DC bias, inelastic tunneling events of single electrons produce a stream of visible photons of plasmonic origin whose superbunching index is 17 (improved to a record of 70 by the authors during publication) when measured with a 53-ps instrumental resolution limit. The effect is driven electrically, rather than optically. This discovery has immediate and profound implications for quantum optics and cryptography, notwithstanding its fundamental importance to basic science and its ushering in of heralded photon experiments on the nanometer scale.
Collapse
Affiliation(s)
- Christopher C. Leon
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, DE-70569 Stuttgart, Germany
- Corresponding author. (C.C.L.); (K.Ku.)
| | - Anna Rosławska
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, DE-70569 Stuttgart, Germany
| | - Abhishek Grewal
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, DE-70569 Stuttgart, Germany
| | - Olle Gunnarsson
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, DE-70569 Stuttgart, Germany
| | - Klaus Kuhnke
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, DE-70569 Stuttgart, Germany
- Corresponding author. (C.C.L.); (K.Ku.)
| | - Klaus Kern
- Max-Planck-Institut für Festkörperforschung, Heisenbergstraße 1, DE-70569 Stuttgart, Germany
- Institut de Physique, École Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland
| |
Collapse
|
19
|
Parzefall M, Szabó Á, Taniguchi T, Watanabe K, Luisier M, Novotny L. Light from van der Waals quantum tunneling devices. Nat Commun 2019; 10:292. [PMID: 30655527 PMCID: PMC6336876 DOI: 10.1038/s41467-018-08266-8] [Citation(s) in RCA: 36] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2018] [Accepted: 12/27/2018] [Indexed: 11/09/2022] Open
Abstract
The understanding of and control over light emission from quantum tunneling has challenged researchers for more than four decades due to the intricate interplay of electrical and optical properties in atomic scale volumes. Here we introduce a device architecture that allows for the disentanglement of electronic and photonic pathways—van der Waals quantum tunneling devices. The electronic properties are defined by a stack of two-dimensional atomic crystals whereas the optical properties are controlled via an external photonic architecture. In van der Waals heterostructures made of gold, hexagonal boron nitride and graphene we find that inelastic tunneling results in the emission of photons and surface plasmon polaritons. By coupling these heterostructures to optical nanocube antennas we achieve resonant enhancement of the photon emission rate in narrow frequency bands by four orders of magnitude. Our results lead the way towards a new generation of nanophotonic devices that are driven by quantum tunneling. Electrical and optical properties of light emitting devices driven by quantum tunneling are closely intertwined. Parzefall et al. show that these properties can be individually controlled by cointegrating van der Waals heterostructures with optical antennas.
Collapse
Affiliation(s)
| | - Áron Szabó
- Integrated Systems Laboratory, ETH Zürich, 8092, Zürich, Switzerland
| | - Takashi Taniguchi
- National Institute for Material Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Kenji Watanabe
- National Institute for Material Science, 1-1 Namiki, Tsukuba, 305-0044, Japan
| | - Mathieu Luisier
- Integrated Systems Laboratory, ETH Zürich, 8092, Zürich, Switzerland
| | - Lukas Novotny
- Photonics Laboratory, ETH Zürich, 8093, Zürich, Switzerland.
| |
Collapse
|
20
|
Février P, Gabelli J. Tunneling time probed by quantum shot noise. Nat Commun 2018; 9:4940. [PMID: 30467389 PMCID: PMC6250673 DOI: 10.1038/s41467-018-07369-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2018] [Accepted: 10/25/2018] [Indexed: 11/08/2022] Open
Abstract
In typical metallic tunnel junctions, the tunneling events occur on a femtosecond timescale. An estimation of this time requires current measurements at optical frequencies and remains challenging. However, it has been known for more than 40 years that as soon as the bias voltage exceeds one volt, the junction emits infrared radiation as an electrically driven optical antenna. We demonstrate here that the photon emission results from the fluctuations of the current inside the tunneling barrier. Photon detection is then equivalent to a measurement of the current fluctuations at optical frequencies, allowing to probe the tunneling time. Based on this idea, we perform optical spectroscopy and electronic current fluctuation measurements in the far from equilibrium regime. Our experimental data are in very good agreement with theoretical predictions based on the Landauer Büttiker scattering formalism. By combining the optics and the electronics, we directly estimate the so-called traversal time.
Collapse
Affiliation(s)
- Pierre Février
- Laboratoire de Physique des Solides, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay, France
| | - Julien Gabelli
- Laboratoire de Physique des Solides, CNRS, Université Paris-Sud, Université Paris-Saclay, 91405, Orsay, France.
| |
Collapse
|
21
|
Möller TB, Ganser A, Kratt M, Dickreuter S, Waitz R, Scheer E, Boneberg J, Leiderer P. Fast quantitative optical detection of heat dissipation by surface plasmon polaritons. NANOSCALE 2018; 10:11894-11900. [PMID: 29897094 DOI: 10.1039/c8nr02489h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Heat management at the nanoscale is an issue of increasing importance. In optoelectronic devices the transport and decay of plasmons contribute to the dissipation of heat. By comparison of experimental data and simulations we demonstrate that it is possible to gain quantitative information about excitation, propagation and decay of surface plasmon polaritons (SPPs) in a thin gold stripe supported by a silicon membrane. The temperature-dependent optical transmissivity of the membrane is used to determine the temperature distribution around the metal stripe with high spatial and temporal resolution. This method is complementary to techniques where the propagation of SPPs is monitored optically, and provides additional information which is not readily accessible by other means. In particular, we demonstrate that the thermal conductivity of the membrane can also be derived from our analysis. The results presented here show the high potential of this tool for heat management studies in nanoscale devices.
Collapse
Affiliation(s)
- Thomas B Möller
- Department of Physics, University of Konstanz, 78457 Konstanz, Germany.
| | | | | | | | | | | | | | | |
Collapse
|
22
|
Ekici E, Kapitza P, Bobisch CA, Möller R. Electron-induced photon emission above the quantum cutoff due to time-energy uncertainty. OPTICS LETTERS 2017; 42:4585-4588. [PMID: 29140318 DOI: 10.1364/ol.42.004585] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Accepted: 10/05/2017] [Indexed: 06/07/2023]
Abstract
The light emission from a tunneling junction induced by tunneling electrons has been studied around the cutoff at hν=eVt. The emitted photons are found to exceed the excitation energy provided by the energy of the tunneling electrons. The experiments have been performed by a low- temperature scanning tunneling microscope at 80 K for an Ag(111) surface and an Ag-covered PtIr tip. A detailed analysis of the emission spectra reveals that the findings cannot be explained by the thermal broadening of the electron Fermi distribution alone. However, a correct description is found if a finite lifetime of the excited states in the range of 30-80 fs is included.
Collapse
|