Dual-frequency terahertz emission from splitting filaments induced by lens tilting in air

Dual-frequency terahertz radiation from air-plasma filaments produced with two-color lasers in air has been demonstrated experimentally. When a focusing lens is tilted for a few degrees, it is shown that the laser filament evolves from a single one to two sub-filaments. Two independent terahertz sources emitted from the sub-filaments with different frequencies and polarizations are identified, where the frequency of terahertz waves from the trailing sub-filament is higher than that from the leading sub-filament.

[1]  H. Hopkins,et al.  Wave theory of aberrations , 1950 .

[2]  Yi Liu,et al.  Strong enhancement of terahertz radiation from laser filaments in air by a static electric field. , 2008, Physical review letters.

[3]  Xu Xie,et al.  Coherent control of THz wave generation in ambient air. , 2006, Physical review letters.

[4]  J. Daigle,et al.  Lens tilting effect on filamentation and filament-induced fluorescence , 2009 .

[5]  F. Théberge,et al.  Elliptically polarized terahertz emission in the forward direction of a femtosecond laser filament in air , 2008 .

[6]  John H. Booske,et al.  Plasma physics and related challenges of millimeter-wave-to-terahertz and high power microwave generationa) , 2008 .

[7]  N. Karpowicz,et al.  Terahertz emission profile from laser-induced air plasma , 2006 .

[8]  See Leang Chin,et al.  Terahertz emission from a dc-biased two-color femtosecond laser-induced filament in air , 2010 .

[9]  Alexander Pukhov,et al.  Theoretical analysis and simulations of strong terahertz radiation from the interaction of ultrashort laser pulses with gases. , 2008, Physical review. E, Statistical, nonlinear, and soft matter physics.

[10]  R. Hochstrasser,et al.  Intense terahertz pulses by four-wave rectification in air. , 2000, Optics letters.

[11]  George Rodriguez,et al.  Coherent control of terahertz supercontinuum generation in ultrafast laser–gas interactions , 2008 .

[12]  X. Zhang,et al.  Free‐space electro‐optic sampling of terahertz beams , 1995 .

[13]  S. Tzortzakis,et al.  Strong terahertz emission enhancement via femtosecond laser filament concatenation in air. , 2010, Optics letters.

[14]  Olga G. Kosareva,et al.  Characterization of terahertz emission from a dc-biased filament in air , 2009 .

[15]  V. Tikhonchuk,et al.  Conical forward THz emission from femtosecond-laser-beam filamentation in air. , 2007, Physical review letters.

[16]  Z. Sheng,et al.  Terahertz radiation by two-color lasers due to the field ionization of gases , 2013 .

[17]  George Rodriguez,et al.  Terahertz emission from ultrafast ionizing air in symmetry-broken laser fields. , 2007, Optics express.

[18]  P Di Trapani,et al.  Terahertz pulse emission optimization from tailored femtosecond laser pulse filamentation in air. , 2009, Optics letters.

[19]  F. Théberge,et al.  Elliptically polarized Terahertz emission through four-wave mixing in a two-color filament in air , 2009 .

[20]  F. Théberge,et al.  Ultrafast birefringence induced by a femtosecond laser filament in gases. , 2009, Optics letters.

[21]  Hartmut G. Roskos,et al.  Generation of terahertz pulses by photoionization of electrically biased air , 2000 .

[22]  White,et al.  Subpicosecond, electromagnetic pulses from intense laser-plasma interaction. , 1993, Physical review letters.

[23]  A. Mysyrowicz,et al.  Polarization analysis of terahertz radiation generated by four-wave mixing in air. , 2008, Optics letters.

[24]  Hartmut G. Roskos,et al.  Broadband THz emission from gas plasmas induced by femtosecond optical pulses: From fundamentals to applications , 2007 .