175 citations · 703 across the 19 of their papers we have counts for
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Generation of elliptically polarized nitrogen-ion laser fields using two-color femtosecond laser pulses
Ziting Li, Bin Zeng, Wei Chu +6
We experimentally investigate generation of molecular nitrogen-ion lasers with two femtosecond laser pulses at different wavelengths. The first pulse serves as the pump which ioniz…
Time-resolved shadowgraphs of transient plasma induced by spatiotemporally focused femtosecond laser pulses in fused silica glass
Zhaohui Wang, Bin Zeng, Guihua Li +7
We report on experimental observations of formation and evolution of transient plasma produced in fused silica glass with spatiotemporally focused (STF) femtosecond laser pulses us…
Non-perturbative generation of above-threshold harmonics from pre-excited argon atoms in intense mid-infrared laser fields
Guihua Li, Hongqiang Xie, Ziting Li +4
We experimentally investigate the generation of above-threshold harmonics completely from argon atoms on an excited state using mid-infrared femtosecond laser pulses. The highly no…
Population Redistribution among Multiple Electronic States of Molecular Nitrogen Ions in Strong Laser Fields
Jinping Yao, Shicheng Jiang, Wei Chu +11
We carry out a combined theoretical and experimental investigation on the population distributions in the ground and excited states of tunnel ionized N2 molecules at various driver…
Spatiotemporal focusing does not always improve axial intensity localization
Ya Cheng, Hongqiang Xie, Zhaohui Wang +6
We report on an experimental comparison on critical intensities of nonlinear self-focusing in air with conventional focusing and spatiotemporal focusing schemes. Our results show t…
Backward air lasing actions induced by femtosecond laser filamentation: influence of population inversion lifetime
Hongqiang Xie, Guihua Li, Wei chu +5
We experimentally investigate generation of backward 357 nm N2 laser in a gas mixture of N2/Ar using 800-nm femtosecond laser pulses, and examine the involved gain dynamics based o…
Interferometric characterization of pulse front tilt of spatiotemporally focused femtosecond laser pulses for three-dimensional micromachining application
Zhaohui Wang, Fei He, Jielei Ni +6
We report on an experimental measurement of the pulse front tilt (PFT) of spatiotemporally focused femtosecond laser pulses in the focal plane in both air and bulk transparent mate…
Gain dynamics of a free-space nitrogen laser pumped by circularly polarized femtosecond laser pulses
Jinping Yao, Hongqiang Xie, Bin Zeng +9
We experimentally demonstrate ultrafast dynamic of generation of a strong 337-nm nitrogen laser by injecting an external seed pulse into a femtosecond laser filament pumped by a ci…
Impulsive rotational Raman scattering of N2 by a remote "air laser" in femtosecond laser filament
Jielei Ni, Wei Chu, Haisu Zhang +8
We report on experimental realization of impulsive rotational Raman scattering from neutral nitrogen molecules in a femtosecond laser filament using an intense self-induced white-l…
Real-time observation of dynamics in rotational molecular wave packets by use of "air laser" spectroscopy
Bin Zeng, Wei Chu, Guihua Li +6
Molecular rotational spectroscopy based on strong-field-ionization-induced nitrogen laser is employed to investigate the time evolution of the rotational wave packet composed by a…
Second harmonic generation in a centrosymmetric gas medium with spatiotemporally focused intense femtosecond laser pulses
Guihua Li, Jielei Ni, Hongqiang Xie +9
We demonstrate unexpectedly strong second harmonic generation (SHG) in Argon gas by use of spatiotemporally focused (SF) femtosecond laser pulses. The resulting SHG by the SF schem…
Signature of superradiance from a nitrogen gas plasma channel produced by strong field ionization
Guihua Li, Chenrui Jing, Bin Zeng +8
Recently, Yao et al. demonstrated the creation of coherent emissions in nitrogen gas with two-color (800 nm + 400 nm) ultrafast laser pulses [New J. Phys. 15, 023046 (2013)]. Based…
Self-induced white-light seeding laser in a femtosecond laser filament
Wei Chu, Guihua Li, Hongqiang Xie +8
We report, for what we believe to be the first time, on the generation of remote self-seeding laser amplification by using only one 800 nm Ti:Sapphire femtosecond laser pulse. The…
Remote creation of strong and coherent emissions in air with two-color ultrafast laser pulses
Jinping Yao, Guihua Li, Chenrui Jing +11
We experimentally demonstrate generation of strong narrow-bandwidth emissions with excellent coherent properties at ~391 nm and ~428 nm from molecular ions of nitrogen inside a fem…