Hostname: page-component-cd9895bd7-dzt6s Total loading time: 0 Render date: 2024-12-26T04:03:01.018Z Has data issue: false hasContentIssue false

Transient setting of relativistic ponderomotive non-linearity and filamentation of ultra-short laser pulses in collisionless plasmas

Published online by Cambridge University Press:  11 July 2019

R.P. Sharma
Affiliation:
Centre for Energy Studies, Indian Institute of Technology, Delhi-110016, India
Narender Kumar*
Affiliation:
Centre for Energy Studies, Indian Institute of Technology, Delhi-110016, India Department of Physics, Sri Venkateswara College, University of Delhi, New Delhi-110021, India
R. Uma
Affiliation:
Centre for Energy Studies, Indian Institute of Technology, Delhi-110016, India
Ram Kishor Singh
Affiliation:
Department of Physics, Shivpati Post Graduate College, Siddharth University, Siddharth Nagar-272205, India
P.K. Gupta
Affiliation:
Centre for Energy Studies, Indian Institute of Technology, Delhi-110016, India
*
Author for correspondence: Narender Kumar, Centre for Energy Studies, Indian Institute of Technology, Delhi-110016, India, E-mail: [email protected]

Abstract

We study the setting up of relativistic ponderomotive non-linearity in an under-dense collisionless cold plasma. Using the fluid model, coupled system of equations of the laser beam and electron plasma oscillations has been derived. We present the numerical simulation for this coupled system of equations, when the coupling arises through relativistic ponderomotive non-linearity. The filamentation of the laser beam has been found to vary appreciably with perturbation wave number. The results show that with time, localized structures become more complex and the plasma oscillation frequency spectra have several harmonic peaks at terahertz frequencies when the electron plasma frequency is in terahertz range and laser frequency is around 2.35 × 1015 rad/s. We also present the semi-analytical model to capture the underlying physics.

Type
Research Article
Copyright
Copyright © Cambridge University Press 2019 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Adak, A, Blackman, DR, Chatterjee, , Singh, PK, Lad, AD, Brijesh, P, Robinson, APL, Pasley, J and Kumar, GR (2014) Ultrafast dynamics of a near-solid-density layer in an intense femtosecond laser-excited plasma. Physics of Plasmas 21, 062704.Google Scholar
Adak, A, Robinson, APL, Singh, PK, Chatterjee, G, Lad, AD, Pasley, J and Kumar, GR (2015) Terahertz acoustics in hot dense laser plasmas. Physical Review Letters 114, 115001.Google Scholar
Akhmanov, SA, Sukhorukov, AP and Khokhlov, RV (1968) Self-focusing and diffraction of light in a nonlinear medium. Soviet Physics Uspekhi 10, 609.Google Scholar
Brandi, HS, Manus, C and Mainfray, G (1993) Relativistic and ponderomotive self-focusing of a laser beam in a radially inhomogeneous plasma. I. Paraxial approximation. Physics of Fluids B: Plasma Physics 5, 3539.Google Scholar
Canuto, C, Hussaini, MY, Quarteroni, A and Zang, TA (1988) Spectral Methods in Fluid Dynamics. New York: Springer-Verlag.Google Scholar
Chen, XL and Sudan, RN (1993) Necessary and sufficient conditions for self-focusing of short ultraintense laser pulse in underdense plasma. Physical Review Letters 70, 20822085.Google Scholar
Feit, MD, Komashko, AM and Rubenchik, AM (2001) Relativistic self-focusing in underdense plasma. Physica D 152–153, 705713.Google Scholar
Ginzburg, VL (1970) The Propagation of Electromagnetic Waves in Plasmas. New York: Pergamon.Google Scholar
Hussain, S, Sharma, S, Singh, RK, Uma, R and Sharma, RP (2017) Numerical simulation to study transient self-focusing and gigahertz acoustic generation in collisional plasma. Plasma Physics 24, 052103.Google Scholar
Kaw, PK, Schmidt, G and Wilcox, T (1973) Filamentation and trapping of electromagnetic radiation in plasma. Physics of Fluids 16, 15221525.Google Scholar
Kruer, WL (1974) The Physics of Laser Plasma Interaction. New York: Addison-Wesley.Google Scholar
Liu, CS and Tripathi, VK (1986) Consequence of filamentation on stimulated Raman scattering. Physics of Fluids 29, 4188.Google Scholar
Malka, V, Modena, J, Nazmudin, Z, Danger, AE, Clayton, CE, Marsh, KA, Joshi, C, Danson, C, Neely, D and Walsh, FN (1997) Second harmonic generation and its interaction with relativistic plasma waves driven by forward Raman instability in underdense plasmas. Physics of Plasmas 4, 1127.Google Scholar
Modena, A, Najmudin, Z, Clayton, CE, Marsh, KA, Joshi, C, Malka, V, Darrow, CB, Danson, C, Neely, D and Walsh, FN (1995) Electron acceleration from the breaking of relativistic plasma waves. Nature 377, 606.Google Scholar
Mulser, P and Bauer, D (2010) High Power Laser–Matter Interaction. Berlin, Heidelberg: Springer-Verlag.Google Scholar
Ozaki, T, Elouga, LBB, Ganeev, R, Kieffer, JC, Suzuki, M and Kuroda, H (2007) Intense harmonic generation from Silver ablation. Laser and Particle Beams 25, 321.Google Scholar
Pukhov, A and Meyer-ter-Vehn, J (2002) Laser wake field acceleration: the highly non-linear broken-wave regime. Applied Physics B: Photophysics and Laser Chemistry 74, 355.Google Scholar
Sharma, RP, Hussain, S and Gaur, N (2015) Numerical simulation to study the transient self focusing of laser beam in plasma. Physics of Plasmas 22, 022107.Google Scholar
Sharma, S, Kumar, N, Hussain, S and Sharma, RP (2017) Nonlinear evolution of the filamentation instability and chaos in laser–plasma interaction. Laser and Particle Beams 35, 1018.Google Scholar
Sodha, MS, Ghatak, AK and Tripathi, VK (1976) Self focusing of laser beams in plasmas and semiconductors. Progress in Optics E 3, 169265.Google Scholar
Sprangle, P, Esarey, E and Ting, A (1990) Nonlinear theory of intense laser-plasma interactions. Physical Review Letters 64, 2011.Google Scholar
Umstadter, D (2003) Relativistic laser–plasma interactions. Journal of Physics D: Applied Physics 36, 151–165.Google Scholar