Influence of the Terahertz Field on the Processes of Low- and High-Order Harmonic Generation by Femtosecond Laser Pulses in a Gaseous Medium

IF 1.3 4区物理与天体物理 Q3 PHYSICS, MULTIDISCIPLINARY

JETP Letters Pub Date : 2025-07-18 DOI:10.1134/S0021364025606712

P. A. Shulyndin, B. V. Rumiantsev, E. A. Migal, A. V. Pushkin, F. V. Potemkin

{"title":"Influence of the Terahertz Field on the Processes of Low- and High-Order Harmonic Generation by Femtosecond Laser Pulses in a Gaseous Medium","authors":"P. A. Shulyndin, B. V. Rumiantsev, E. A. Migal, A. V. Pushkin, F. V. Potemkin","doi":"10.1134/S0021364025606712","DOIUrl":null,"url":null,"abstract":"<p>The influence of a strong (up to 7.5 MV/cm) terahertz field on the processes of low (2–5 eV) and high (55‒83 eV) order harmonic generation of the near-infrared radiation with a wavelength of 1.24 μm under the excitation of an argon jet has been experimentally investigated. It has been shown that the quasistatic terahertz field leads to the appearance of even low- and high-order harmonics, which is due to the violation of the spatial symmetry of the atomic potential in the first case and to the terahertz-induced breaking of the infrared waveform symmetry in the second case. It has been experimentally observed that the terahertz field leads to the simultaneous modulation of the intensity of both even and odd high-order harmonics, while a change in the intensity of low-order harmonics has been observed only for even components. Even low (2nd) and high (70th) order harmonics demonstrate different power-law dependences on the terahertz field strength under an increase in the infrared pulse energy, which is due to the appearance of additional radiation at the frequency of the second harmonic under the formation of laser-induced plasma.</p>","PeriodicalId":604,"journal":{"name":"JETP Letters","volume":"121 11","pages":"846 - 852"},"PeriodicalIF":1.3000,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1134/S0021364025606712.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"JETP Letters","FirstCategoryId":"101","ListUrlMain":"https://link.springer.com/article/10.1134/S0021364025606712","RegionNum":4,"RegionCategory":"物理与天体物理","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"PHYSICS, MULTIDISCIPLINARY","Score":null,"Total":0}

引用次数: 0

Abstract

The influence of a strong (up to 7.5 MV/cm) terahertz field on the processes of low (2–5 eV) and high (55‒83 eV) order harmonic generation of the near-infrared radiation with a wavelength of 1.24 μm under the excitation of an argon jet has been experimentally investigated. It has been shown that the quasistatic terahertz field leads to the appearance of even low- and high-order harmonics, which is due to the violation of the spatial symmetry of the atomic potential in the first case and to the terahertz-induced breaking of the infrared waveform symmetry in the second case. It has been experimentally observed that the terahertz field leads to the simultaneous modulation of the intensity of both even and odd high-order harmonics, while a change in the intensity of low-order harmonics has been observed only for even components. Even low (2nd) and high (70th) order harmonics demonstrate different power-law dependences on the terahertz field strength under an increase in the infrared pulse energy, which is due to the appearance of additional radiation at the frequency of the second harmonic under the formation of laser-induced plasma.

查看原文本刊更多论文

太赫兹场对飞秒激光脉冲在气体介质中产生低次和高次谐波过程的影响

实验研究了强（7.5 MV/cm）太赫兹场对波长为1.24 μm的近红外辐射在氩射流激发下低（2-5 eV）和高（55-83 eV）次谐波产生过程的影响。结果表明，准静态太赫兹场会导致低次谐波和高次谐波的出现，这是由于第一种情况下原子势的空间对称性被破坏，而第二种情况下太赫兹场会导致红外波形对称性的破坏。实验观察到，太赫兹场导致偶次和奇次高次谐波强度的同时调制，而低次谐波强度的变化只在偶次分量中观察到。在红外脉冲能量增加的情况下，低(2)阶和高（70）阶谐波也表现出不同的幂律依赖于太赫兹场强，这是由于在激光诱导等离子体形成的二次谐波频率下出现了额外的辐射。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

求助全文

约1分钟内获得全文求助全文

来源期刊

JETP Letters 物理-物理：综合

CiteScore

2.40

自引率

30.80%

发文量

164

审稿时长

3-6 weeks

期刊介绍： All topics of experimental and theoretical physics including gravitation, field theory, elementary particles and nuclei, plasma, nonlinear phenomena, condensed matter, superconductivity, superfluidity, lasers, and surfaces.