Effect of preformed plasma on terahertz-wave emission from the plasma generated by two-color laser pulses

Journal Article · Tue Feb 15 00:00:00 EST 2011 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.83.023828· OSTI ID:21537238

Minami, Yasuo; Nakajima, Makoto; Suemoto, Tohru ^[1]

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1. Institute for Solid State Physics, University of Tokyo, Kashiwanoha 5-1-5, Kashiwa-shi, Chiba, 277-8581 (Japan)

We introduced a weak prepulse 0-2 ns before the main pulse in the formation of a terahertz (THz) wave in air plasma by laser pulses composed of fundamental and second-harmonic waves. The prepulse suppressed the THz wave generated by the main pulse. We analyzed the suppression factor as a function of the time interval between the prepulse and the main pulse and found that the THz wave from the main pulse decreases immediately after the prepulse, recovers partially within several hundred picoseconds, and then recovers slowly. This suppression is attributed to the dense plasma, which absorbs and screens the generated THz wave, since the relaxation time is close to the lifetime of the fluorescence from the plasma. The results support the idea that the major mechanism of THz wave generation is explained by the plasma current model.

• OSTI ID: 21537238
• Journal Information: Physical Review. A, Vol. 83, Issue 2; Other Information: DOI: 10.1103/PhysRevA.83.023828; (c) 2011 American Institute of Physics; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
73 NUCLEAR PHYSICS AND RADIATION PHYSICS
AIR
COLOR
ELECTRIC CURRENTS
FLUORESCENCE
LASER-PRODUCED PLASMA
LIFETIME
PULSES
RELAXATION TIME
THZ RANGE
TIME DEPENDENCE
WAVE PROPAGATION
CURRENTS
EMISSION
FLUIDS
FREQUENCY RANGE
GASES
LUMINESCENCE
OPTICAL PROPERTIES
ORGANOLEPTIC PROPERTIES
PHOTON EMISSION
PHYSICAL PROPERTIES
PLASMA