1
|
Wu Y, Wang Y, Bao D, Deng X, Zhang S, Yu-Chun L, Ke S, Liu J, Liu Y, Wang Z, Ham P, Hanna A, Pan J, Hu X, Li Z, Zhou J, Wang C. Emerging probing perspective of two-dimensional materials physics: terahertz emission spectroscopy. LIGHT, SCIENCE & APPLICATIONS 2024; 13:146. [PMID: 38951490 PMCID: PMC11217405 DOI: 10.1038/s41377-024-01486-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2023] [Revised: 04/09/2024] [Accepted: 05/15/2024] [Indexed: 07/03/2024]
Abstract
Terahertz (THz) emission spectroscopy (TES) has emerged as a highly effective and versatile technique for investigating the photoelectric properties of diverse materials and nonlinear physical processes in the past few decades. Concurrently, research on two-dimensional (2D) materials has experienced substantial growth due to their atomically thin structures, exceptional mechanical and optoelectronic properties, and the potential for applications in flexible electronics, sensing, and nanoelectronics. Specifically, these materials offer advantages such as tunable bandgap, high carrier mobility, wideband optical absorption, and relatively short carrier lifetime. By applying TES to investigate the 2D materials, their interfaces and heterostructures, rich information about the interplay among photons, charges, phonons and spins can be unfolded, which provides fundamental understanding for future applications. Thus it is timely to review the nonlinear processes underlying THz emission in 2D materials including optical rectification, photon-drag, high-order harmonic generation and spin-to-charge conversion, showcasing the rich diversity of the TES employed to unravel the complex nature of these materials. Typical applications based on THz emissions, such as THz lasers, ultrafast imaging and biosensors, are also discussed. Step further, we analyzed the unique advantages of spintronic terahertz emitters and the future technological advancements in the development of new THz generation mechanisms leading to advanced THz sources characterized by wide bandwidth, high power and integration, suitable for industrial and commercial applications. The continuous advancement and integration of TES with the study of 2D materials and heterostructures promise to revolutionize research in different areas, including basic materials physics, novel optoelectronic devices, and chips for post-Moore's era.
Collapse
Affiliation(s)
- Yifei Wu
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Yuqi Wang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Di Bao
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Xiaonan Deng
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Simian Zhang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Lin Yu-Chun
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Shengxian Ke
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Jianing Liu
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Yingjie Liu
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Zeli Wang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Pingren Ham
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Andrew Hanna
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Jiaming Pan
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Xinyue Hu
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Zhengcao Li
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Ji Zhou
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China
| | - Chen Wang
- State Key Laboratory of New Ceramics and Fine Processing, Key Laboratory of Advanced Materials of Ministry of Education, School of Materials Science and Engineering, Tsinghua University, 100084, Beijing, China.
- Beijing Advanced Innovation Center for Integrated Circuits, 100084, Beijing, China.
| |
Collapse
|
2
|
Li Q, Mei L, Bi K, Hou L, Zhang S, Han S, Guo M, Zhang S, Wu D, Mu J, Chou X. Tunable terahertz absorption of ion gel-graphene hybrids based on the Salisbury effect. OPTICS EXPRESS 2024; 32:11838-11848. [PMID: 38571022 DOI: 10.1364/oe.519866] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Accepted: 03/01/2024] [Indexed: 04/05/2024]
Abstract
The gate-tunable absorption properties of graphene make it suitable for terahertz (THz) absorbers. However, the realization of a graphene-based THz absorber faces challenges between the difficulty of patterning graphene for processing and the intrinsically low absorbance of graphene with the high electric field needed to change the conductivity of graphene. This report presents an electrically tunable graphene THz absorber where a single-layer graphene film and a gold reflective layer are separated by a polyimide (PI) dielectric layer to form an easily fabricated three-layer Salisbury screen structure. The carrier density of the graphene layer can be efficiently tuned by a small external electrical gating (-5V-5 V) with the assistance of an ion gel layer. The voltage modulation of the Fermi energy level (EF) of graphene was confirmed by Raman spectra, and the variation of the device absorbance was confirmed using a THz time-domain spectroscopy system (THz-TDS). The measurements show that the EF is adjusted in the range of 0-0.5 eV, and THz absorbance is adjusted in the range of 60%-99%. The absorber performs well under different curvatures, and the peak absorbance is all over 95%. We conducted further analysis of the absorber absorbance by varying the thickness of the PI dielectric layer, aiming to examine the correlation between the resonant frequency of the absorber and the dielectric layer thickness. Our research findings indicate that the proposed absorber holds significant potential for application in diverse fields such as communication, medicine, and sensing.
Collapse
|
3
|
Balos V, Wolf M, Kovalev S, Sajadi M. Optical rectification and electro-optic sampling in quartz. OPTICS EXPRESS 2023; 31:13317-13327. [PMID: 37157471 DOI: 10.1364/oe.480339] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
We report the electro-optic sampling (EOS) response and the terahertz (THz) optical rectification (OR) of the z-cut α-quartz. Due to its small effective second-order nonlinearity, large transparency window and hardness, freestanding thin quartz plates can faithfully measure the waveform of intense THz pulses with MV/cm electric-field strength. We show that both its OR and EOS responses are broad with extension up to ∼8 THz. Strikingly, the latter responses are independent of the crystal thickness, a plausible indication of dominant surface contribution to the total second-order nonlinear susceptibility of quartz at THz frequencies. Our study introduces the crystalline quartz as a reliable THz electro-optic medium for high field THz detection, and characterize its emission as a common substrate.
Collapse
|
4
|
Aftab S, Hegazy HH, Iqbal MZ. Recent advances in 2D TMD circular photo-galvanic effects. NANOSCALE 2023; 15:3651-3665. [PMID: 36734944 DOI: 10.1039/d2nr05337c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Two-dimensional (2D) layered semiconductors are appealing materials for high-specific-power photovoltaic systems due to their unique optoelectronic properties. The 2D materials can be naturally thin, and their properties can be altered in a variety of ways. Therefore, these materials may be used to develop high-performance opto-spintronic and photovoltaic devices. The most recent and promising strategies were used to induce circular photo-galvanic effects (CPGEs) in 2D TMD materials with broken inversion symmetry. The majority of quantum devices were manufactured by mechanical exfoliation to investigate the electrical behavior of ultrathin 2D materials. The investigation of CPGEs in 2D materials could enable the exploration of spin-polarized optoelectronics to produce more energy-efficient computing systems. The current research on nanomaterial-based materials paves the way for developing materials to store, manipulate, and transmit information with better performance. Finally, this study concludes by summarizing the current challenges and prospects.
Collapse
Affiliation(s)
- Sikandar Aftab
- Department of Intelligent Mechatronics Engineering, Sejong University, Seoul 05006, South Korea.
| | - Hosameldin Helmy Hegazy
- Research Center for Advanced Materials Science (RCAMS), King Khalid University, Abha 61413, P. O. Box 9004, Saudi Arabia
- Department of Physics, Faculty of Science, King Khalid University, P.O. Box 9004, Abha, Saudi Arabia
| | - Muhammad Zahir Iqbal
- Faculty of Engineering Sciences, Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi 23640, Khyber Pakhtunkhwa, Pakistan
| |
Collapse
|
5
|
Real-time observation of the buildup of polaron in α-FAPbI 3. Nat Commun 2023; 14:917. [PMID: 36801865 PMCID: PMC9938110 DOI: 10.1038/s41467-023-36652-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2022] [Accepted: 02/10/2023] [Indexed: 02/19/2023] Open
Abstract
The formation of polaron, i.e., the strong coupling process between the carrier and lattice, is considered to play a crucial role in benefiting the photoelectric performance of hybrid organic-inorganic halide perovskites. However, direct observation of the dynamical formation of polarons occurring at time scales within hundreds of femtoseconds remains a technical challenge. Here, by terahertz emission spectroscopy, we demonstrate the real-time observation of polaron formation process in FAPbI3 films. Two different polaron resonances interpreted with the anharmonic coupling emission model have been studied: P1 at ~1 THz relates to the inorganic sublattice vibration mode and the P2 at ~0.4 THz peak relates to the FA+ cation rotation mode. Moreover, P2 could be further strengthened than P1 by pumping the hot carriers to the higher sub-conduction band. Our observations could open a door for THz emission spectroscopy to be a powerful tool in studying polaron formation dynamics in perovskites.
Collapse
|
6
|
Cheng L, Xiong Y, Kang L, Gao Y, Chang Q, Chen M, Qi J, Yang H, Liu Z, Song JC, Chia EE. Giant photon momentum locked THz emission in a centrosymmetric Dirac semimetal. SCIENCE ADVANCES 2023; 9:eadd7856. [PMID: 36598995 PMCID: PMC9812375 DOI: 10.1126/sciadv.add7856] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Accepted: 11/28/2022] [Indexed: 06/17/2023]
Abstract
Strong second-order optical nonlinearities often require broken material centrosymmetry, thereby limiting the type and quality of materials used for nonlinear optical devices. Here, we report a giant and highly tunable terahertz (THz) emission from thin polycrystalline films of the centrosymmetric Dirac semimetal PtSe2. Our PtSe2 THz emission is turned on at oblique incidence and locked to the photon momentum of the incident pump beam. Notably, we find an emitted THz efficiency that is giant: It is two orders of magnitude larger than the standard THz-generating nonlinear crystal ZnTe and has values approaching that of the noncentrosymmetric topological material TaAs. Further, PtSe2 THz emission displays THz sign and amplitude that is controlled by the incident pump polarization and helicity state even as optical absorption is only weakly polarization dependent and helicity independent. Our work demonstrates how photon drag can activate pronounced optical nonlinearities that are available even in centrosymmetric Dirac materials.
Collapse
Affiliation(s)
- Liang Cheng
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
- State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Ying Xiong
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Lixing Kang
- Division of Advanced Materials, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China
| | - Yu Gao
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Qing Chang
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Mengji Chen
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore
| | - Jingbo Qi
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu 610054, China
- State Key Laboratory of Electronic Thin Films and Integrated Devices, University of Electronic Science and Technology of China, Chengdu 610054, China
| | - Hyunsoo Yang
- Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576, Singapore
| | - Zheng Liu
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 637371, Singapore
| | - Justin C.W. Song
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Elbert E. M. Chia
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| |
Collapse
|
7
|
Li Q, Bi K, Niu Y, Zhou S, Tan L, Mu J, Han S, Zhang S, Geng W, Mei L, Chou X. Modulation of graphene THz absorption based on HAuCl 4 doping method. OPTICS EXPRESS 2022; 30:40482-40490. [PMID: 36298980 DOI: 10.1364/oe.475103] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/07/2022] [Accepted: 10/11/2022] [Indexed: 06/16/2023]
Abstract
Graphene is an attractive material for terahertz (THz) absorbers because of its tunable Fermi-Level (EF). It has become a research hotspot to modulate the EF of graphene and THz absorption of graphene. Here, a sandwich-structured single layer graphene (SLG)/ Polyimide (PI)/Au THz absorber was proposed, and top-layer graphene was doped by HAuCl4 solutions. The EF of graphene was shifted by HAuCl4 doping, which was characterized by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and Raman tests. The results showed that the EF is shifted about 0.42 eV under 100 mM HAuCl4 doping, the sheet resistance is reduced from 1065 Ω/sq (undoped) to 375 Ω/sq (100 mM). The corresponding absorbance was increased from 40% to 80% at 0.65 THz and increased from 50% to 90% at 2.0 THz under 100 mM HAuCl4 doping. Detailed studies showed that the absorption came from a sandwich structure that meets the impedance matching requirements and provided a thin resonant cavity to capture the incident THz waves. In addition, not only the absorber can be prepared simply, but its results in experiments and simulations agree as well. The proposed device can be applied to electromagnetic shielding and imaging, and the proposed method can be applied to prepare other graphene-based devices.
Collapse
|
8
|
Gerasimenko AY, Kuksin AV, Shaman YP, Kitsyuk EP, Fedorova YO, Murashko DT, Shamanaev AA, Eganova EM, Sysa AV, Savelyev MS, Telyshev DV, Pavlov AA, Glukhova OE. Hybrid Carbon Nanotubes-Graphene Nanostructures: Modeling, Formation, Characterization. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12162812. [PMID: 36014677 PMCID: PMC9412346 DOI: 10.3390/nano12162812] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/31/2022] [Revised: 08/12/2022] [Accepted: 08/13/2022] [Indexed: 06/06/2023]
Abstract
A technology for the formation and bonding with a substrate of hybrid carbon nanostructures from single-walled carbon nanotubes (SWCNT) and reduced graphene oxide (rGO) by laser radiation is proposed. Molecular dynamics modeling by the real-time time-dependent density functional tight-binding (TD-DFTB) method made it possible to reveal the mechanism of field emission centers formation in carbon nanostructures layers. Laser radiation stimulates the formation of graphene-nanotube covalent contacts and also induces a dipole moment of hybrid nanostructures, which ensures their orientation along the force lines of the radiation field. The main mechanical and emission characteristics of the formed hybrid nanostructures were determined. By Raman spectroscopy, the effect of laser radiation energy on the defectiveness of all types of layers formed from nanostructures was determined. Laser exposure increased the hardness of all samples more than twice. Maximum hardness was obtained for hybrid nanostructure with a buffer layer (bl) of rGO and the main layer of SWCNT-rGO(bl)-SWCNT and was 54.4 GPa. In addition, the adhesion of rGO to the substrate and electron transport between the substrate and rGO(bl)-SWCNT increased. The rGO(bl)-SWCNT cathode with an area of ~1 mm2 showed a field emission current density of 562 mA/cm2 and stability for 9 h at a current of 1 mA. The developed technology for the formation of hybrid nanostructures can be used both to create high-performance and stable field emission cathodes and in other applications where nanomaterials coating with good adhesion, strength, and electrical conductivity is required.
Collapse
Affiliation(s)
- Alexander Yu. Gerasimenko
- Institute of Biomedical Systems, National Research University of Electronic Technology MIET, Shokin Square 1, 124498 Moscow, Russia
- Institute for Bionic Technologies and Engineering, I.M. Sechenov First Moscow State Medical University, Bolshaya Pirogovskaya Street 2-4, 119991 Moscow, Russia
| | - Artem V. Kuksin
- Institute of Biomedical Systems, National Research University of Electronic Technology MIET, Shokin Square 1, 124498 Moscow, Russia
| | - Yury P. Shaman
- Scientific-Manufacturing Complex “Technological Centre”, Shokin Square 1, bld. 7 off. 7237, 124498 Moscow, Russia
- Institute of Nanotechnology of Microelectronics of the Russian Academy of Sciences, Leninsky Prospekt 32A, 119991 Moscow, Russia
| | - Evgeny P. Kitsyuk
- Scientific-Manufacturing Complex “Technological Centre”, Shokin Square 1, bld. 7 off. 7237, 124498 Moscow, Russia
| | - Yulia O. Fedorova
- Institute of Biomedical Systems, National Research University of Electronic Technology MIET, Shokin Square 1, 124498 Moscow, Russia
- Scientific-Manufacturing Complex “Technological Centre”, Shokin Square 1, bld. 7 off. 7237, 124498 Moscow, Russia
| | - Denis T. Murashko
- Institute of Biomedical Systems, National Research University of Electronic Technology MIET, Shokin Square 1, 124498 Moscow, Russia
| | - Artemiy A. Shamanaev
- Scientific-Manufacturing Complex “Technological Centre”, Shokin Square 1, bld. 7 off. 7237, 124498 Moscow, Russia
| | - Elena M. Eganova
- Institute of Nanotechnology of Microelectronics of the Russian Academy of Sciences, Leninsky Prospekt 32A, 119991 Moscow, Russia
| | - Artem V. Sysa
- Scientific-Manufacturing Complex “Technological Centre”, Shokin Square 1, bld. 7 off. 7237, 124498 Moscow, Russia
| | - Mikhail S. Savelyev
- Institute of Biomedical Systems, National Research University of Electronic Technology MIET, Shokin Square 1, 124498 Moscow, Russia
- Institute for Regenerative Medicine, I.M. Sechenov First Moscow State Medical University, Bolshaya Pirogovskaya Street 2-4, 119991 Moscow, Russia
| | - Dmitry V. Telyshev
- Institute of Biomedical Systems, National Research University of Electronic Technology MIET, Shokin Square 1, 124498 Moscow, Russia
- Institute for Bionic Technologies and Engineering, I.M. Sechenov First Moscow State Medical University, Bolshaya Pirogovskaya Street 2-4, 119991 Moscow, Russia
| | - Alexander A. Pavlov
- Institute of Nanotechnology of Microelectronics of the Russian Academy of Sciences, Leninsky Prospekt 32A, 119991 Moscow, Russia
| | - Olga E. Glukhova
- Institute for Bionic Technologies and Engineering, I.M. Sechenov First Moscow State Medical University, Bolshaya Pirogovskaya Street 2-4, 119991 Moscow, Russia
- Department of Physics, Saratov State University, Astrakhanskaya Street 83, 410012 Saratov, Russia
| |
Collapse
|
9
|
Enhancement of Terahertz Radiation by Surface Plasmons Based on CdTe Thin Films. NANOMATERIALS 2022; 12:nano12020290. [PMID: 35055307 PMCID: PMC8779331 DOI: 10.3390/nano12020290] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/11/2021] [Revised: 01/06/2022] [Accepted: 01/12/2022] [Indexed: 02/01/2023]
Abstract
Terahertz (THz) time-domain spectroscopy (TDS) is a powerful tool used to characterize the surface/interface of materials, and semiconductor/metal interfaces can generate THz emission through ultrafast optical excitation, which can be further improved through the optical excitation of surface plasmons. Here, we assembled cadmium telluride (CdTe) on an AuAg alloy (Au25Ag75, wt.%) substrate and obtained five times stronger THz emission compared with silicon substrate, and found that the enhancement can be tuned by controlling the thickness of the semiconductor materials and plasmonic metal substrates. We believe that our results not only promote the development of THz emission enhancement, but also provide a straightforward way of producing small, thin, and more efficient terahertz photonic devices.
Collapse
|
10
|
Xi F, Yang H, Khayrudinov V, He Y, Haggren T, Zhou Y, Lipsanen H, Sun Z, Xu X. Enhanced terahertz emission from mushroom-shaped InAs nanowire network induced by linear and nonlinear optical effects. NANOTECHNOLOGY 2021; 33:085207. [PMID: 34768252 DOI: 10.1088/1361-6528/ac3948] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/18/2021] [Accepted: 11/12/2021] [Indexed: 06/13/2023]
Abstract
The development of powerful terahertz (THz) emitters is the cornerstone for future THz applications, such as communication, medical biology, non-destructive inspection, and scientific research. Here, we report the THz emission properties and mechanisms of mushroom-shaped InAs nanowire (NW) network using linearly polarized laser excitation. By investigating the dependence of THz signal to the incidence pump light properties (e.g. incident angle, direction, fluence, and polarization angle), we conclude that the THz wave emission from the InAs NW network is induced by the combination of linear and nonlinear optical effects. The former is a transient photocurrent accelerated by the photo-Dember field, while the latter is related to the resonant optical rectification effect. Moreover, thep-polarized THz wave emission component is governed by the linear optical effect with a proportion of ∼85% and the nonlinear optical effect of ∼15%. In comparison, thes-polarized THz wave emission component is mainly decided by the nonlinear optical effect. The THz emission is speculated to be enhanced by the localized surface plasmon resonance absorption of the In droplets on top of the NWs. This work verifies the nonlinear optical mechanism in the THz generation of semiconductor NWs and provides an enlightening reference for the structural design of powerful and flexible THz surface and interface emitters in transmission geometry.
Collapse
Affiliation(s)
- Fugang Xi
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710127, People's Republic of China
| | - He Yang
- School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100191, People's Republic of China
- Department of Electronics and Nanoengineering, Aalto University, Espoo, PO Box 13500, FI-00076, Finland
| | - Vladislav Khayrudinov
- Department of Electronics and Nanoengineering, Aalto University, Espoo, PO Box 13500, FI-00076, Finland
| | - Yuhang He
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710127, People's Republic of China
| | - Tuomas Haggren
- Department of Electronics and Nanoengineering, Aalto University, Espoo, PO Box 13500, FI-00076, Finland
| | - Yixuan Zhou
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710127, People's Republic of China
| | - Harri Lipsanen
- Department of Electronics and Nanoengineering, Aalto University, Espoo, PO Box 13500, FI-00076, Finland
| | - Zhipei Sun
- Department of Electronics and Nanoengineering, Aalto University, Espoo, PO Box 13500, FI-00076, Finland
| | - Xinlong Xu
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710127, People's Republic of China
| |
Collapse
|
11
|
Wang H, Chang J, Huang Y, Lei Z, Du W, Zhou Y, E Y, Xu X. Large In-Plane Anisotropic Terahertz Emission Induced by Asymmetric Polarization in Low-Symmetric PdSe 2. ACS APPLIED MATERIALS & INTERFACES 2021; 13:54543-54550. [PMID: 34734685 DOI: 10.1021/acsami.1c16197] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Palladium diselenide (PdSe2) exhibits air stability, low symmetry, and high carrier mobility, resulting in unique in-plane anisotropy for polarized optoelectronic devices. However, the relationship of the symmetry and the terahertz (THz) radiation remains elusive yet significant for both the THz source in technology and nonlinear optical physics in science. Herein, we observed large in-plane anisotropic THz radiation from multilayer PdSe2 under femtosecond laser excitation. The THz emission demonstrates 2α dependence on the optical polarization angle from the resonant optical rectification combined with a background from the photocarrier acceleration under the surface depletion field. Interestingly, the in-plane THz emission along and perpendicular to the puckered direction demonstrates large anisotropy. Furthermore, the THz time-domain signals exhibit reversed polarities along the positive and negative puckered directions. This asymmetric polarization could relate to the bonding of Pd-Se, resulting in the unidirectional photon-induced current. Our results bridge the gap between the low-symmetry two-dimensional materials and the THz technology, which could promote the development of THz-polarized devices based on low-symmetry layered materials.
Collapse
Affiliation(s)
- He Wang
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710127, China
| | - Jiawei Chang
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710127, China
| | - Yuanyuan Huang
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710127, China
| | - Zhen Lei
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710127, China
| | - Wanyi Du
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710127, China
| | - Yixuan Zhou
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710127, China
| | - Yiwen E
- The Institute of Optics, University of Rochester, Rochester, New York 14627, United States
| | - Xinlong Xu
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710127, China
| |
Collapse
|
12
|
Saushin AS, Mikheev GM, Vanyukov VV, Svirko YP. The Surface Photogalvanic and Photon Drag Effects in Ag/Pd Metal-Semiconductor Nanocomposite. NANOMATERIALS 2021; 11:nano11112827. [PMID: 34835592 PMCID: PMC8623762 DOI: 10.3390/nano11112827] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 10/19/2021] [Accepted: 10/21/2021] [Indexed: 11/16/2022]
Abstract
We performed the investigation of the polarization-sensitive photocurrent generated in silver-palladium metal-semiconductor nanocomposite films under irradiation with nanosecond laser pulses at the wavelength of 2600 nm. It is shown that in both the transverse and the longitudinal configuration, the surface photogalvanic (SPGE) and photon drag effects (PDE) contribute to the observed photocurrent. However, the temporal profile of the transverse photocurrent pulse is monopolar at any polarization and angle of incidence, while the temporal profile of the longitudinal photocurrent pulse depends on the polarization of the excitation beam. Specifically, the irradiation of the film with the s-polarized excitation beam produces a monopolar photoresponse, while at p-polarized excitation, the photoresponse is bipolar, having a short front and long tail. Obtained experimental results are in agreement with the developed phenomenological theory, which describes transverse and longitudinal photocurrents due to SPGE and PDE in terms of relevant second-order nonlinear susceptibilities and allows us to obtain their dependences on the angle of incidence and polarization of the excitation laser beam. The pronounced dependence of the photocurrent on the angle of incidence and polarization of the excitation beam opens avenues toward the development of polarization- and position-sensitive detectors for industrial and space applications.
Collapse
Affiliation(s)
- Aleksandr S. Saushin
- Institute of Photonics, University of Eastern Finland, FI-80101 Joensuu, Finland; (V.V.V.); (Y.P.S.)
- Institute of Mechanics, Udmurt Federal Research Center of the Russian Academy of Sciences, 426067 Izhevsk, Russia;
- Correspondence:
| | - Gennady M. Mikheev
- Institute of Mechanics, Udmurt Federal Research Center of the Russian Academy of Sciences, 426067 Izhevsk, Russia;
| | - Viatcheslav V. Vanyukov
- Institute of Photonics, University of Eastern Finland, FI-80101 Joensuu, Finland; (V.V.V.); (Y.P.S.)
| | - Yuri P. Svirko
- Institute of Photonics, University of Eastern Finland, FI-80101 Joensuu, Finland; (V.V.V.); (Y.P.S.)
| |
Collapse
|
13
|
Chang J, Wang H, Lei Z, Du W, Huang Y, Zhou Y, Zhu L, Xu X. Coherent Elliptically Polarized Terahertz Wave Generation in WSe 2 by Linearly Polarized Femtosecond Laser Excitation. J Phys Chem Lett 2021; 12:10068-10078. [PMID: 34623821 DOI: 10.1021/acs.jpclett.1c02770] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Coherent polarization control of terahertz (THz) wave radiation in both the time-domain and the frequency-domain is significant in information technology, material science, and spectroscopic analysis. Elliptically polarized THz radiation is generally limited to chiral materials induced by circularly polarized light excitation. Herein, we demonstrate the coherent elliptically polarized THz radiation from few-layer tungsten diselenide (WSe2) in both the time-domain and the frequency-domain under linearly polarized femtosecond laser excitation. This coherent elliptical THz radiation is mainly dominated by in-plane anisotropic shift current and out-of-plane drift current, which is verified by the THz radiation dependence on the pump laser polarization angles, incident angles, and sample azimuthal angles systematically. The ellipticity and major axis direction of the elliptical THz wave can be efficiently controlled by either pump light polarization or sample azimuthal angle due to the controllable amplitudes and phases of two coherent orthogonal THz wave components. Our finding provides a method to distinguish drift and shift photocurrents in different directions and offers a unique design concept for elliptical THz generation with two-dimensional (2D) material physics.
Collapse
Affiliation(s)
- Jiawei Chang
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Xi'an 710069, China
| | - He Wang
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Xi'an 710069, China
| | - Zhen Lei
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Xi'an 710069, China
| | - Wanyi Du
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Xi'an 710069, China
| | - Yuanyuan Huang
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Xi'an 710069, China
| | - Yixuan Zhou
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Xi'an 710069, China
| | - Lipeng Zhu
- School of Electronic Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121, China
| | - Xinlong Xu
- Shaanxi Joint Lab of Graphene, State Key Laboratory of Photon-Technology in Western China Energy, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Xi'an 710069, China
| |
Collapse
|
14
|
Wu F, Long Y, Li H, Chen Y, Pan M, Wu X. Frequency-tunable terahertz angular selectivity based on a dielectric-graphene multilayer structure. APPLIED OPTICS 2021; 60:2811-2816. [PMID: 33798156 DOI: 10.1364/ao.419723] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 03/06/2021] [Indexed: 06/12/2023]
Abstract
To achieve frequency-tunable angular selectivity at terahertz frequencies, a tunable epsilon-near-zero (ENZ) metamaterial based on a subwavelength dielectric-graphene multilayer structure is designed. The ENZ frequency of the dielectric-graphene multilayer can be dynamically tuned by the gate voltage applied to graphene. Transmittance angular spectra show that only the incident lights close to normal incidence can propagate through the structure while other incident lights cannot, which indicates that our structure can be utilized for frequency-tunable terahertz angular selection. The optimal directivity D reaches 183 and the transmittance at normal incidence reaches 0.462. This multilayer-based tunable terahertz ENZ metamaterial will possess potential application prospects in tunable highly directive antennas.
Collapse
|
15
|
Zheng W, Zhao X, Fu W. Review of Vertical Graphene and its Applications. ACS APPLIED MATERIALS & INTERFACES 2021; 13:9561-9579. [PMID: 33616394 DOI: 10.1021/acsami.0c19188] [Citation(s) in RCA: 23] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
Vertical graphene (VG) is a thin-film complex material featuring hierarchical microstructures: graphene-containing carbon nanosheets growing vertically on its deposition substrate, few-layer graphene basal layers, and chemically active atomistic defect sites and edges. Thanks to the fundamental characteristics of graphene materials, e.g. excellent electrical conductivity, thermal conductivity, chemical stability, and large specific surface area, VG materials have been successfully implemented into various niche applications which are strongly associated with their unique morphology. The microstructure of VG materials can be tuned by modifying growth methods and the parameters of growth processes. Multiple growth processes have been developed to address faster, safer, and mass production methods of VG materials, as well as accommodating various applications. VG's successful applications include field emission, supercapacitors, fuel cells, batteries, gas sensors, biochemical sensors, electrochemical analysis, strain sensors, wearable electronics, photo trapping, terahertz emission, etc. Research topics on VG have been more diversified in recent years, indicating extensive attention from the research community and great commercial value. In this review article, VG's morphology is briefly reviewed, and then various growth processes are discussed from the perspective of plasma science. After that, the most recent progress in its applications and related sciences and technologies are discussed.
Collapse
Affiliation(s)
- Wei Zheng
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China
- William and Mary Research Institute, College of William and Mary, Williamsburg, Virginia 23187, United States
| | - Xin Zhao
- William and Mary Research Institute, College of William and Mary, Williamsburg, Virginia 23187, United States
| | - Wenjie Fu
- School of Electronic Science and Engineering, University of Electronic Science and Technology of China, Chengdu, Sichuan 610054, China
- William and Mary Research Institute, College of William and Mary, Williamsburg, Virginia 23187, United States
| |
Collapse
|
16
|
Mikheev GM, Kogai VY, Mikheev KG, Mogileva TN, Saushin AS, Svirko YP. Interaction of polarization-sensitive surface photocurrents in semitransparent CuSe/Se film. OPTICS EXPRESS 2021; 29:2112-2123. [PMID: 33726412 DOI: 10.1364/oe.415043] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2020] [Accepted: 12/11/2020] [Indexed: 06/12/2023]
Abstract
We demonstrate that the transverse polarization-sensitive photoresponse of the CuSe/Se nanocomposite film deposited on a transparent substrate depends on whether the film is irradiated from the air side or substrate side. In particular, the nanosecond photocurrent pulse is either bipolar or unipolar pulse depending on which interface beam hits first. The observed phenomenon can be described in terms of the interplay between counter-propagating photocurrents generated at the air/nanocomposite and substrate/nanocomposite interfaces due to the surface photogalvanic effect. Our experimental findings can be employed to control the amplitude and temporal profile of the photoresponse by changing the polarization of the excitation laser beam.
Collapse
|
17
|
Fan Z, Xu M, Huang Y, Lei Z, Zheng L, Zhang Z, Zhao W, Zhou Y, Wang X, Xu X, Liu Z. Terahertz Surface Emission from MoSe 2 at the Monolayer Limit. ACS APPLIED MATERIALS & INTERFACES 2020; 12:48161-48169. [PMID: 32990422 DOI: 10.1021/acsami.0c13474] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The surface-charge region of bulk and monolayer MoSe2 is analyzed directly by terahertz (THz) surface emission spectroscopy in a nondestructive way. Both surface nonlinear optical polarization and surface field-induced photocurrent contribute to the THz radiation in both bulk and monolayer MoSe2. The first THz emission mechanism is due to the surface optical rectification and the second one is due to the photogenerated carriers accelerated by the surface depletion field. The THz radiation contribution from the surface optical rectification is basically the same for both bulk and monolayer MoSe2 because of the same symmetry at the surface. However, the contribution from the surface field-induced photocurrent is ∼94.2% in bulk MoSe2 and it goes down to 74.5% in monolayer MoSe2. This is due to the larger surface depletion field in bulk MoSe2 (∼2.54 × 107 V/m) compared with that in monolayer MoSe2 (∼5.42 × 105 V/m), as such THz emission from the bulk is approximately four times larger than that from monolayer MoSe2. This work not only proves the clear THz radiation mechanism from MoSe2 crystals but also affords a THz technology for the surface characterization of two-dimensional materials.
Collapse
Affiliation(s)
- Zeyu Fan
- Shaanxi Joint Lab of Graphene, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710069, China
| | - Manzhang Xu
- School of Information Science and Technology, Northwest University, Xi'an 710127, China
- Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, Xi'an 710072, China
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
| | - Yuanyuan Huang
- Shaanxi Joint Lab of Graphene, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710069, China
| | - Zhen Lei
- Shaanxi Joint Lab of Graphene, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710069, China
| | - Lu Zheng
- Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, Xi'an 710072, China
| | - Zhiyong Zhang
- School of Information Science and Technology, Northwest University, Xi'an 710127, China
| | - Wu Zhao
- School of Information Science and Technology, Northwest University, Xi'an 710127, China
| | - Yixuan Zhou
- Shaanxi Joint Lab of Graphene, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710069, China
| | - Xuewen Wang
- Frontiers Science Center for Flexible Electronics, Xi'an Institute of Flexible Electronics (IFE) and Xi'an Institute of Biomedical Materials & Engineering, Northwestern Polytechnical University, Xi'an 710072, China
| | - Xinlong Xu
- Shaanxi Joint Lab of Graphene, Institute of Photonics & Photon-Technology, School of Physics, Northwest University, Xi'an 710069, China
| | - Zheng Liu
- School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
- Centre for Micro-/Nano-Electronics (NOVITAS), School of Electrical & Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798, Singapore
- CINTRA CNRS/NTU/THALES, UMI 3288, Research Techno Plaza, 50 Nanyang Drive, Singapore 637553, Singapore
| |
Collapse
|
18
|
Otteneder M, Hubmann S, Lu X, Kozlov DA, Golub LE, Watanabe K, Taniguchi T, Efetov DK, Ganichev SD. Terahertz Photogalvanics in Twisted Bilayer Graphene Close to the Second Magic Angle. NANO LETTERS 2020; 20:7152-7158. [PMID: 32915581 DOI: 10.1021/acs.nanolett.0c02474] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
We report on the observation of photogalvanic effects in tBLG with a twist angle of 0.6°. We show that excitation of the tBLG bulk causes a photocurrent, whose sign and magnitude are controlled by the orientation of the radiation electric field and the photon helicity. The observed photocurrent provides evidence for the reduction of the point group symmetry in low twist-angle tBLG to the lowest possible one. The developed theory shows that the current is formed by asymmetric scattering in gyrotropic tBLG. We also detected the photogalvanic current formed in the vicinity of the edges. For both bulk and edge photocurrents, we demonstrate the emergence of pronounced oscillations upon variation of the gate voltage. The gate voltages associated with the oscillations correlate with peaks in resistance measurements. These are well explained by interband transitions between a multitude of isolated bands in tBLG.
Collapse
Affiliation(s)
| | - Stefan Hubmann
- Terahertz Center, University of Regensburg, 93040 Regensburg, Germany
| | - Xiaobo Lu
- ICFO - Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona 08860, Spain
| | - Dmitry A Kozlov
- Rzhanov Institute of Semiconductor Physics, 630090 Novosibirsk, Russia
| | | | - Kenji Watanabe
- Research Center for Functional Materials, National Institute of Materials Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Takashi Taniguchi
- International Center for Materials Nanoarchitectonics, National Institute of Material Science, 1-1 Namiki, Tsukuba 305-0044, Japan
| | - Dmitri K Efetov
- ICFO - Institut de Ciencies Fotoniques, The Barcelona Institute of Science and Technology, Castelldefels, Barcelona 08860, Spain
| | - Sergey D Ganichev
- Terahertz Center, University of Regensburg, 93040 Regensburg, Germany
| |
Collapse
|
19
|
Zonov RG, Mikheev GM, Obraztsov AN, Svirko YP. Circular photocurrent in the carbon nanowall film. OPTICS LETTERS 2020; 45:2022-2025. [PMID: 32236058 DOI: 10.1364/ol.391528] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Accepted: 02/29/2020] [Indexed: 06/11/2023]
Abstract
We report the helicity-dependent photocurrent in the carbon nanowall film synthesized on the silicon substrates by the chemical vapor deposition technique. The film is composed of multilayer graphene flakes grown along the substrate normal. We measured the transverse photocurrent generated in the film under irradiation with nanosecond laser pulses by depositing two conductive electrodes along the plane of incidence. The measurements were performed by using elliptically polarized fundamental, second-, third-, and fourth-harmonics beams of the Nd:YAG laser. We revealed that the shorter the excitation wavelength, the higher the magnitude of the helicity-dependent transverse photocurrent generated in the film. In particular, at wavelengths of 266 and 355 nm, the photocurrent strongly depends on the degree of the circular polarization of the laser beam while, at the wavelength of 1064 nm, the transverse photocurrent is almost helicity independent.
Collapse
|
20
|
Yao Z, Huang Y, Zhu L, Obraztsov PA, Du W, Zhang L, Xu X. Interfacial THz generation from graphene/Si mixed-dimensional van der Waals heterostructure. NANOSCALE 2019; 11:16614-16620. [PMID: 31460543 DOI: 10.1039/c9nr03570b] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Even though Si is the most cost efficient and extensively used semiconductor in modern optoelectronics, it is not considered to be an effective THz emitter due to its low carrier drift velocity and small saturated built-in electric field from the inversion layer. Herein, we present an effective way to enhance THz generation using a graphene/Si Schottky junction (GSSJ) excited with a femtosecond laser under electrical gating without rapid saturation and with high carrier drift velocity. This mixed-dimensional van der Waals interface demonstrates large saturation pump fluence with an invalid inversion layer by removing the native oxide on the Si surface. The THz emission amplitude from GSSJ effectively increases with the gate voltage. The THz emission from GSSJ under the same excitation conditions is stronger than that from the surface of InAs (100) and GaAs (100). The results not only show an efficient THz emission from GSSJ but also demonstrate the ability of THz generation for probing the mixed-dimensional van der Waals interface.
Collapse
Affiliation(s)
- Zehan Yao
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710069, China.
| | - Yuanyuan Huang
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710069, China.
| | - Lipeng Zhu
- School of Electronic Engineering, Xi'an University of Posts and Telecommunications, Xi'an 710121, China
| | - Petr A Obraztsov
- A. M. Prokhorov General Physics Institute, RAS, 38 Vavilov st., Moscow, 119991, Russia.
| | - Wanyi Du
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710069, China.
| | - Longhui Zhang
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710069, China.
| | - Xinlong Xu
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710069, China. and Guangxi Key Laboratory of Automatic Detecting Technology and Instruments, Guilin University of Electronic Technology, Guilin 541004, People's Republic of China
| |
Collapse
|
21
|
Kim HG, Oh IK, Lee S, Jeon S, Choi H, Kim K, Yang JH, Chung JW, Lee J, Kim WH, Lee HBR. Analysis of Defect Recovery in Reduced Graphene Oxide and Its Application as a Heater for Self-Healing Polymers. ACS APPLIED MATERIALS & INTERFACES 2019; 11:16804-16814. [PMID: 30964978 DOI: 10.1021/acsami.8b19955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Reduced graphene oxide (RGO) obtained from graphene oxide has received much attention because of its simple and cost-effective manufacturing process. Previous studies have demonstrated the scalable production of RGO with relatively high quality; however, irreducible defects on RGO deteriorate the unique intrinsic physical properties of graphene, such as high-mobility electrical charge transport, limiting its potential applicability. Using the enhanced chemical reactivity of such defects, atomic layer deposition (ALD) can be a useful method to selectively passivate the defect sites. Herein, we analyzed the selective formation of Pt by ALD on the defect sites of RGO and investigated the effect of Pt formation on the electrical properties of RGO by using ultrafast terahertz (THz) laser spectroscopy. Time-resolved THz measurements directly corroborated that the degree of the defect-recovering property of ALD Pt-treated RGO appearing as Auger-type sub-picosecond relaxation, which is otherwise absent in pristine RGO. In addition, the conductivity improvement of Pt-recovered RGO was theoretically explained by density functional theory calculations. The ALD Pt-passivated RGO yielded a superior platform for the fabrication of a highly conductive and transparent graphene heater. By using the ALD Pt/RGO heater embedded underneath scratched self-healing polymer materials, we also demonstrated the effective recovery property of self-healing polymers with high-performance heating capability. Our work is expected to result in significant advances toward practical applications for RGO-based flexible and transparent electronics.
Collapse
Affiliation(s)
- Hyun Gu Kim
- Department of Materials Science and Engineering , Incheon National University , Incheon 22012 , Korea
| | - Il-Kwon Oh
- School of Electrical and Electronic Engineering , Yonsei University , Seoul 03722 , Korea
| | - Seungmin Lee
- School of Electrical and Electronic Engineering , Yonsei University , Seoul 03722 , Korea
| | - Sera Jeon
- Department of Physics , Pusan National University , Busan 46241 , Korea
| | - Hyunyong Choi
- School of Electrical and Electronic Engineering , Yonsei University , Seoul 03722 , Korea
| | - Kwanpyo Kim
- Department of Physics , Yonsei University , Seoul 03722 , Korea
| | - Joo Ho Yang
- Department of Organic Materials and Fiber Engineering , Soongsil University , Seoul 06978 , Korea
| | - Jae Woo Chung
- Department of Organic Materials and Fiber Engineering , Soongsil University , Seoul 06978 , Korea
| | - Jaekwang Lee
- Department of Physics , Pusan National University , Busan 46241 , Korea
| | - Woo-Hee Kim
- Department of Materials Science and Chemical Engineering , Hanyang University , Ansan 15588 , Korea
| | - Han-Bo-Ram Lee
- Department of Materials Science and Engineering , Incheon National University , Incheon 22012 , Korea
| |
Collapse
|
22
|
He C, Zhao Q, Huang Y, Zhu L, Zhang S, Bai J, Xu X. Nonlinear Optical Response in Graphene/WX 2 (X = S, Se, and Te) van der Waals Heterostructures. J Phys Chem Lett 2019; 10:2090-2100. [PMID: 30973733 DOI: 10.1021/acs.jpclett.9b00217] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Light-frequency conversion based on two-dimensional (2D) materials is of great importance for modern nano- and integrated photonics. Herein, we report both the intrinsic (from the pure WX2 (X = S, Se, and Te)) and extrinsic (from the interface of graphene/WX2) second-order nonlinear coefficient tensor from graphene/WX2 van der Waals (vdW) heterostructures by first-principles calculations. The prominent peaks in the dispersion relation of the intrinsic second-order nonlinear coefficient in monolayer WX2 are due to the Van Hove singularity in the high-symmetry point or along the high-symmetry line with high joint density of states. The enhanced nonlinear optical response in the infrared band can be achieved in graphene/WS2 vdW heterostructures, resulting from the interlayer charge transfer between graphene and WS2. The value of the intrinsic second-order nonlinear coefficients of graphene/WSe2 vdW heterostructures is 1.5 times larger than that of pure monolayer WSe2 at the band gap energy of monolayer WSe2 because of the enhanced carrier generation after the heterostructure formation. Different from pure monolayer WX2, azimuthal angle-dependent second harmonic generation from graphene/WX2 vdW heterostructures exhibits extraordinary rotational symmetry at different photon energies, which can be used to deduce the extrinsic second-order nonlinear coefficient. These results pave the way for the nonlinear optical coefficient design based on 2D heterostructures for nonlinear nanophotonics and integrated devices.
Collapse
Affiliation(s)
- Chuan He
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology , Northwest University , Xi'an 710069 , China
| | - Qiyi Zhao
- School of Science , Xi'an University of Posts & Telecommunications , Xi'an 710121 , China
| | - Yuanyuan Huang
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology , Northwest University , Xi'an 710069 , China
| | - Lipeng Zhu
- School of Electronic Engineering , Xi'an University of Posts & Telecommunications , Xi'an 710121 , China
| | - Sujuan Zhang
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology , Northwest University , Xi'an 710069 , China
| | - Jintao Bai
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology , Northwest University , Xi'an 710069 , China
| | - Xinlong Xu
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology , Northwest University , Xi'an 710069 , China
- Guangxi Key Laboratory of Automatic Detecting Technology and Instruments , Guilin University of Electronic Technology , Guilin 541004 , China
| |
Collapse
|
23
|
Huang Y, Yao Z, He C, Zhu L, Zhang L, Bai J, Xu X. Terahertz surface and interface emission spectroscopy for advanced materials. JOURNAL OF PHYSICS. CONDENSED MATTER : AN INSTITUTE OF PHYSICS JOURNAL 2019; 31:153001. [PMID: 30669133 DOI: 10.1088/1361-648x/ab00c0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Surfaces and interfaces are of particular importance for optoelectronic and photonic materials as they are involved in many physical and chemical processes such as carrier dynamics, charge transfer, chemical bonding, transformation reactions and so on. Terahertz (THz) emission spectroscopy provides a sensitive and nondestructive method for surface or interface analysis of advanced materials ranging from graphene to transition metal dichalcogenides, topological insulators, hybrid perovskites, and mixed-dimensional heterostructures based on 2D materials. In this review paper, we start with the THz radiation mechanisms under ultrafast laser excitation. Then we concentrate on the recent progresses of THz emission spectroscopy on the surface and interface properties of advanced materials, including transient surface photocurrents, surface nonlinear polarization, surface states, interface potential, and gas molecule adsorption/desorption processes. This novel spectroscopic method can not only promote the development of new and compact THz sources, but also provide a nondestructive optical method for surface and interface characterization of photocurrent and nonlinear polarization dynamics of materials.
Collapse
Affiliation(s)
- Yuanyuan Huang
- Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics and Photon-Technology, Northwest University, Xi'an 710069, People's Republic of China
| | | | | | | | | | | | | |
Collapse
|
24
|
Mikheev GM, Saushin AS, Styapshin VM, Svirko YP. Interplay of the photon drag and the surface photogalvanic effects in the metal-semiconductor nanocomposite. Sci Rep 2018; 8:8644. [PMID: 29872143 PMCID: PMC5988816 DOI: 10.1038/s41598-018-26923-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 05/04/2018] [Indexed: 11/23/2022] Open
Abstract
Photon drag effect (PDE) and surface photogalvanic effect (SPGE) can be observed in centrosymmetric media and manifest themselves in photocurrents, the magnitude and polarity of which depend on wavevector and polarization of the excitation laser beam. PDE photocurrent originates from the transfer of the photon momentum to a free charge carrier, while SPGE photocurrent is due to diffuse scattering of the photoexcited carriers in the subsurface layer. However, despite the different underlying physical mechanisms, these photocurrents have almost indistinguishable dependencies on the polarization and the angle of incidence of the excitation laser beam. In this paper, we observe for the first time a competition between PDE and SPGE in the film containing metal (Ag-Pd) and semiconductor (PdO) nanocrystallites. We show that, depending on the angle of incidence, polarization azimuth and wavelength of the excitation laser beam, the interplay of the PDE and SPGE leads to the generation of either monopolar or bipolar nanosecond current pulses. The experiments performed allow us to visualize the contributions both these effects and obtain light-to-current conversion efficiency in a wide spectral range. Our experimental findings can be employed to control the magnitude and polarity of the light-induced current by polarization of the excitation laser beam.
Collapse
Affiliation(s)
- G M Mikheev
- Institute of Mechanics, Udmurt Federal Research Center of the UB RAS, Izhevsk, 426067, Russia
| | - A S Saushin
- Institute of Mechanics, Udmurt Federal Research Center of the UB RAS, Izhevsk, 426067, Russia
| | - V M Styapshin
- Institute of Mechanics, Udmurt Federal Research Center of the UB RAS, Izhevsk, 426067, Russia
| | - Yu P Svirko
- Institute of Photonics, University of Eastern Finland, Joensuu, 80101, Finland.
| |
Collapse
|