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Li ZL, Bian XB. Terahertz radiation induced by shift currents in liquids. Proc Natl Acad Sci U S A 2024; 121:e2315297121. [PMID: 38377191 PMCID: PMC10907241 DOI: 10.1073/pnas.2315297121] [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: 09/03/2023] [Accepted: 01/03/2024] [Indexed: 02/22/2024] Open
Abstract
Considerable progress has been made in the experimental studies on laser-induced terahertz (THz) radiation in liquids. Liquid THz demonstrates many unique features different from the gas and plasma THz. For example, the liquid THz can be efficiently produced by a monochromatic laser. Its yield is maximized with a longer driving-pulse duration. It is also linearly dependent on the excitation pulse energy. In two-color laser fields, an unexpected unmodulated THz field was measured, and its energy dependence of the driving laser is completely different from that of the modulated THz waves. However, the underlying microscopic mechanism is still unclear due to the difficulties in the description of ultrafast dynamics in complex disordered liquids. Here we propose a shift-current model. The experimental observations could be reproduced by our theory successfully. In addition, our theory could be further utilized to investigate the nuclear quantum effect in the THz radiation in H2O and D2O. This work provides fundamental insights into the origin of the THz radiation in bulk liquids.
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Affiliation(s)
- Zheng-Liang Li
- Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan430071, China
- School of Physical Sciences, University of Chinese Academy of Sciences, Beijing100049, China
| | - Xue-Bin Bian
- Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan430071, China
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2
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Kumar M, Song HS, Lee J, Park D, Suk H, Hur MS. Intense multicycle THz pulse generation from laser-produced nanoplasmas. Sci Rep 2023; 13:4233. [PMID: 36918732 PMCID: PMC10015041 DOI: 10.1038/s41598-023-31427-9] [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: 12/13/2022] [Accepted: 03/11/2023] [Indexed: 03/16/2023] Open
Abstract
We present a novel scheme to obtain robust, narrowband, and tunable THz emission using a nano-dimensional overdense plasma target, irradiated by two counter-propagating detuned laser pulses. So far, no narrowband THz sources with a field strength of GV/m-level have been reported from laser-solid interaction (mostly half-or single-cycle THz pulses with only broadband frequency spectrum). From two- and three-dimensional particle-in-cell simulations, we find that the strong plasma current generated by the beat ponderomotive force in the colliding region, produces beat-frequency radiation in the THz range. Here we report intense THz pulses [Formula: see text]THz) with an unprecedentedly high peak field strength of 11.9 GV/m and spectral width [Formula: see text], which leads to a regime of an extremely bright narrowband THz source of TW/cm[Formula: see text], suitable for various ambitious applications.
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Affiliation(s)
- Manoj Kumar
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Hyung Seon Song
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Jaeho Lee
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Dohyun Park
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea
| | - Hyyong Suk
- Department of Physics and Photon Science, Gwangju Institute of Science and Technology, Gwangju, 61005, Republic of Korea
| | - Min Sup Hur
- Department of Physics, Ulsan National Institute of Science and Technology, Ulsan, 44919, Republic of Korea.
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3
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Bae LJ, Kang GB, Kim M, Lee GS, Sohn JH, Nam CH, Cho BI. Diagnosis of ultrafast surface dynamics of thin foil targets irradiated by intense laser pulses. OPTICS EXPRESS 2023; 31:5767-5776. [PMID: 36823849 DOI: 10.1364/oe.474759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2022] [Accepted: 01/17/2023] [Indexed: 06/18/2023]
Abstract
The temporal modulation of an electron bunch train accelerated from a foil target irradiated by an intense laser pulse is studied by measuring the coherent transition radiation (CTR) from the rear surface of a target. We experimentally obtained CTR spectra from a 1 µm thick foil target irradiated at a maximum intensity of 6.5 × 1019 W/cm2. Spectral redshifts of the emitted radiation corresponding to increases in laser intensity were observed. These measurements were compared with the theoretical calculation of CTR spectra considering ultrafast surface dynamics, such as plasma surface oscillation and relativistically induced transparency. Plasma surface oscillations induce a spectral redshift, while relativistic transparency causes a spectral blueshift. Both effects are required to find reasonable agreement with the experiment over the entire range of laser intensities.
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4
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Lei HY, Sun FZ, Wang TZ, Chen H, Wang D, Wei YY, Ma JL, Liao GQ, Li YT. Highly efficient generation of GV/m-level terahertz pulses from intense femtosecond laser-foil interactions. iScience 2022; 25:104336. [PMID: 35602940 PMCID: PMC9118729 DOI: 10.1016/j.isci.2022.104336] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 04/06/2022] [Accepted: 04/27/2022] [Indexed: 11/05/2022] Open
Abstract
The terahertz radiation from ultraintense laser-produced plasmas has aroused increasing attention recently as a promising approach toward strong terahertz sources. Here, we present the highly efficient production of millijoule-level terahertz pulses, from the rear side of a metal foil irradiated by a 10-TW femtosecond laser pulse. By characterizing the terahertz and electron emission in combination with particle-in-cell simulations, the physical reasons behind the efficient terahertz generation are discussed. The resulting focused terahertz electric field strength reaches over 2 GV/m, which is justified by experiments on terahertz strong-field-driven nonlinearity in semiconductors. Ultraintense laser-foil interactions generate a 2.1-mJ strong terahertz pulse Nearly 1% generation efficiency originates from optimized laser-plasma conditions 2-GV/m high THz fields induce absorption bleaching and impact ionization
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Affiliation(s)
- Hong-Yi Lei
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Fang-Zheng Sun
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Tian-Ze Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Hao Chen
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Dan Wang
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yan-Yu Wei
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jing-Long Ma
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Guo-Qian Liao
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, China
| | - Yu-Tong Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,School of Physical Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.,Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, China.,Collaborative Innovation Center of IFSA (CICIFSA), Shanghai Jiao Tong University, Shanghai 200240, China
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5
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Woldegeorgis A, Herzer S, Almassarani M, Marathapalli S, Gopal A. Modeling terahertz emission from the target rear side during intense laser-solid interactions. Phys Rev E 2019; 100:053204. [PMID: 31869893 DOI: 10.1103/physreve.100.053204] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2019] [Indexed: 11/07/2022]
Abstract
Relativistic laser-solid target interaction is a powerful source of terahertz radiation where broadband terahertz radiation is emitted from the front and rear surfaces of the target. Even though several experimental works have reported the generation of subpicosecond duration gigawatt peak power terahertz pulses from the target rear surface, the underlying physical process behind their origin is still an open question. Here we discuss a numerical model that can accurately reproduce several aspects of the experimental results. The model is based on the charged particle dynamics at the target rear surface and the evolution of the charge separation field. We identify the major contributors that are responsible for broadband terahertz emission from the rear surface of the target.
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Affiliation(s)
- A Woldegeorgis
- Institute of Optics and Quantum Electronics, Max-Wien platz 1, 07743 Jena, Germany.,Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena, Germany
| | - S Herzer
- Institute of Optics and Quantum Electronics, Max-Wien platz 1, 07743 Jena, Germany
| | - M Almassarani
- Institute of Optics and Quantum Electronics, Max-Wien platz 1, 07743 Jena, Germany.,Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena, Germany
| | - S Marathapalli
- Institute of Optics and Quantum Electronics, Max-Wien platz 1, 07743 Jena, Germany
| | - A Gopal
- Institute of Optics and Quantum Electronics, Max-Wien platz 1, 07743 Jena, Germany.,Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena, Germany
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6
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Gopal A, Woldegeorgis A, Herzer S, Almassarani M. Spatiotemporal visualization of the terahertz emission during high-power laser-matter interaction. Phys Rev E 2019; 100:053203. [PMID: 31869948 DOI: 10.1103/physreve.100.053203] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2019] [Indexed: 11/07/2022]
Abstract
Single-cycle pulses with multimillion volts per centimeter field strengths and spectra in the terahertz (THz) band have attracted great interest due to their ability to coherently manipulate molecular orientations and electron spins resonantly and nonresonantly. The tremendous progress made in the development of compact and powerful terahertz sources have identified intense laser-thin foil interaction as a potential candidate for high-power broadband terahertz radiation. They are micrometers in size and deliver radially polarized terahertz pulses with millijoule energy and gigawatt peak power. Although several works have been carried out to investigate the terahertz generation process, their origin and angular distribution are still debated. We present here an indisputable study on their spatiotemporal characteristics and elaborate the underlying physical processes via recording the three-dimensional beam profile along with transient dynamics. These results are substructured with the quantitative visualization of the charge particle spectra.
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Affiliation(s)
- A Gopal
- Institut für Optik und Quantenelektronik, Physikalisch-Astronomische Fakultät, Friedrich-Schiller-Universität, Max-Wien Platz 1, D-07743 Jena, Germany.,Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena, Germany
| | - A Woldegeorgis
- Institut für Optik und Quantenelektronik, Physikalisch-Astronomische Fakultät, Friedrich-Schiller-Universität, Max-Wien Platz 1, D-07743 Jena, Germany.,Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena, Germany
| | - S Herzer
- Institut für Optik und Quantenelektronik, Physikalisch-Astronomische Fakultät, Friedrich-Schiller-Universität, Max-Wien Platz 1, D-07743 Jena, Germany
| | - M Almassarani
- Institut für Optik und Quantenelektronik, Physikalisch-Astronomische Fakultät, Friedrich-Schiller-Universität, Max-Wien Platz 1, D-07743 Jena, Germany.,Helmholtz Institute Jena, Fröbelstieg 3, 07743 Jena, Germany
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7
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Mondal S, Wei Q, Ding WJ, Hafez HA, Fareed MA, Laramée A, Ropagnol X, Zhang G, Sun S, Sheng ZM, Zhang J, Ozaki T. Aligned copper nanorod arrays for highly efficient generation of intense ultra-broadband THz pulses. Sci Rep 2017; 7:40058. [PMID: 28071764 PMCID: PMC5223118 DOI: 10.1038/srep40058] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 11/29/2016] [Indexed: 11/17/2022] Open
Abstract
We demonstrate an intense broadband terahertz (THz) source based on the interaction of relativistic-intensity femtosecond lasers with aligned copper nanorod array targets. For copper nanorod targets with a length of 5 μm, a maximum 13.8 times enhancement in the THz pulse energy (in ≤20 THz spectral range) is measured as compared to that with a thick plane copper target under the same laser conditions. A further increase in the nanorod length leads to a decrease in the THz pulse energy at medium frequencies (≤20 THz) and increase of the electromagnetic pulse energy in the high-frequency range (from 20–200 THz). For the latter, we measure a maximum energy enhancement of 28 times for the nanorod targets with a length of 60 μm. Particle-in-cell simulations reveal that THz pulses are mostly generated by coherent transition radiation of laser produced hot electrons, which are efficiently enhanced with the use of nanorod targets. Good agreement is found between the simulation and experimental results.
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Affiliation(s)
- S Mondal
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
| | - Q Wei
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
| | - W J Ding
- A*STAR Institute of High Performance Computing, Singapore 138632
| | - H A Hafez
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada.,Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany.,Physics Department, Faculty of Science, Helwan University, 11792, Cairo, Egypt
| | - M A Fareed
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
| | - A Laramée
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
| | - X Ropagnol
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
| | - G Zhang
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
| | - S Sun
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
| | - Z M Sheng
- SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG, UK.,Laboratory for Laser Plasmas and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.,Collaborative Innovation Center of IFSA, Shanghai Jiao Tong University, Shanghai 200240, China
| | - J Zhang
- Laboratory for Laser Plasmas and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.,Collaborative Innovation Center of IFSA, Shanghai Jiao Tong University, Shanghai 200240, China
| | - T Ozaki
- Institut national de la recherche scientifique - Centre Energie, Matériaux et Télécommunications (INRS-EMT), 1650 Lionel-Boulet, Varennes, Québec J3X 1S2, Canada
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8
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Ding WJ, Sheng ZM. Sub GV/cm terahertz radiation from relativistic laser-solid interactions via coherent transition radiation. Phys Rev E 2016; 93:063204. [PMID: 27415374 DOI: 10.1103/physreve.93.063204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2016] [Indexed: 11/07/2022]
Abstract
Broadband terahertz (THz) radiation with extremely high peak power, generated by the interaction of a femtosecond laser with a thin solid target, has been investigated via particle-in-cell simulations. The spatial (angular) and temporal profiles of the THz radiation reveal that it is caused by the coherent transition radiation emitted when laser-produced hot electrons pass through the front or rear surface of the target. Dependence of the THz radiation on laser and target parameters is studied; it is shown to have a strong correlation with hot electron production. The THz radiation conversion efficiency can be as high as a few times 10^{-3}. This radiation is not only a potentially high power THz source, but may also be used as a unique diagnostic of hot electron generation and transport in relativistic laser-solid interactions.
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Affiliation(s)
- W J Ding
- A*STAR Institute of High Performance Computing, Singapore 138632
| | - Z M Sheng
- SUPA, Department of Physics, University of Strathclyde, Glasgow G4 0NG, United Kingdom.,Key Laboratory for Laser Plasmas (MoE) and Department of Physics and Astronomy, Shanghai Jiao Tong University, Shanghai 200240, China.,Collaborative Innovation Center of IFSA, Shanghai Jiao Tong University, Shanghai 200240, China
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9
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Li C, Liao GQ, Zhou ML, Du F, Ma JL, Li YT, Wang WM, Sheng ZM, Chen LM, Zhang J. Backward terahertz radiation from intense laser-solid interactions. OPTICS EXPRESS 2016; 24:4010-4021. [PMID: 26907053 DOI: 10.1364/oe.24.004010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We report a systematic study on backward terahertz (THz) radiation generation from laser-solid interactions by changing a variety of laser/plasma parameters. We demonstrate a high-energy (with an energy flux density reaching 80 μJ/sr), broadband (>10 THz) plasma-based radiation source. The radiation energy is mainly distributed either in the >10 THz or <3 THz regions. A radial surface current formed by the lateral transport of low-energy electrons (LEE) is believed to be responsible for the radiation in the high-THz region (>10 THz), while high-energy surface fast electrons (SFE) accelerated along the target surface mainly contribute to lower frequency (<3 THz) radiation. The unifying explanation could be applied to backward THz radiation generation from solid targets with presence of relative small preplasmas.
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10
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Li C, Cui YQ, Zhou ML, Du F, Li YT, Wang WM, Chen LM, Sheng ZM, Ma JL, Lu X, Zhang J. Role of resonance absorption in terahertz radiation generation from solid targets. OPTICS EXPRESS 2014; 22:11797-11803. [PMID: 24921301 DOI: 10.1364/oe.22.011797] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The interaction of 100-fs laser pulses with solid targets at laser intensities 10(16)-10(18)W/cm(2) has been investigated experimentally by simultaneous measurements of terahertz (THz) and second harmonic signals. THz yield at the front side of the target, which rises from the self-organized transient electron currents along the target surface, is found scaling linearly with the laser intensity basically. Measurements of specularly reflected light spectrum show clear evidence of resonance absorption. The positive effects of resonance absorption on surface current and THz radiation generation have been confirmed by two-dimensional (2D) particle-in-cell (PIC) simulations and angular-dependent experiments, respectively.
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11
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Gopal A, Singh P, Herzer S, Reinhard A, Schmidt A, Dillner U, May T, Meyer HG, Ziegler W, Paulus GG. Characterization of 700 μJ T rays generated during high-power laser solid interaction. OPTICS LETTERS 2013; 38:4705-4707. [PMID: 24322111 DOI: 10.1364/ol.38.004705] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Laser-produced solid density plasmas are well-known as table-top sources of electromagnetic radiation. Recent studies have shown that energetic broadband terahertz pulses (T rays) can also be generated from laser-driven compact ion accelerators. Here we report the measurement of record-breaking T-Ray pulses with energies no less than 0.7 mJ. The terahertz spectrum has been characterized for frequencies ranging from 0.1-133 THz. The dependence of T-Ray yield on incident laser energy is linear and shows no tendencies of saturation. The noncollinear emission pattern and the high yield reveal that the T rays are generated by the transient field at the rear surface of the solid target.
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12
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Gopal A, Herzer S, Schmidt A, Singh P, Reinhard A, Ziegler W, Brömmel D, Karmakar A, Gibbon P, Dillner U, May T, Meyer HG, Paulus GG. Observation of gigawatt-class THz pulses from a compact laser-driven particle accelerator. PHYSICAL REVIEW LETTERS 2013; 111:074802. [PMID: 23992071 DOI: 10.1103/physrevlett.111.074802] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Indexed: 06/02/2023]
Abstract
We report the observation of subpicosecond terahertz (T-ray) pulses with energies ≥460 μJ from a laser-driven ion accelerator, thus rendering the peak power of the source higher even than that of state-of-the-art synchrotrons. Experiments were performed with intense laser pulses (up to 5×10(19) W/cm(2)) to irradiate thin metal foil targets. Ion spectra measured simultaneously showed a square law dependence of the T-ray yield on particle number. Two-dimensional particle-in-cell simulations show the presence of transient currents at the target rear surface which could be responsible for the strong T-ray emission.
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Affiliation(s)
- A Gopal
- Institute of Optics and Quantumelectronics, Friedrich-Schiller-Universität Jena, Jena, Germany.
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