jun.liu - Publications List

Takayoshi Kobayashi Lab

West building, Room No:205 

Department of Applied Physics and Chemistry and Institute for Laser 

Science, University of Electro-Communications, Chofugaoka 1-5-1, 

Chofu, Tokyo 182-8585 Japan 

phone +81-42-443-5846 

fax    +81-42-443-5826 

e-mail  jliu@ils.uec.ac.jp

ywkm5314@gmail.com

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Date of birth：July 16, 1979, Male

AREAS OF RESEARCH AND INTERESTS:
• Ultrashort laser and ultrashort laser physics
• High field laser physics
• Femtosecond spectroscopy
• Optical characterization of materials
• Non-linear optics and spectroscopy
• Ultrafast dynamics of nanostructures and optics waveguide in transparent media.

EDUCATION/ TRAINING:

* 3/2007-present: Postdoc, Department of Applied Physics and Chemistry and Institute for Laser Science,
University of Electro-Communications, Tokyo, Japan

* 10/2003-3/2007: Ph.D. in Physics/Optical Engineer, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai, China.
Thesis Title: "High average power amplification，shaping and compression of ultrashort laser pulses."

* 03/2002-03/2003: Student and Research Assistant, Research Center of Laser Fusion of China Academy of Engineering Physics, Mianyang, China.

* 09/2000-07/2003: M.S. in Optics, Northwest University, Xi’an, China.
Thesis Title: "Theoretical and Experimental Study of Ultrashort Pulse Laser Amplification." (including CPA and OPCPA).

* 09/1996-07/2000: B.S. in Optical Engineer, Northwest University, Xi’an, China.

Abstract: Wavelength-tunable multicolored femtosecond laser pulses were generated simultaneously through cascade four-wave mixing in a fused-silica glass plate using two crossing femtosecond laser beams. The wavelength of the sidebands can be continuously tuned from UV to IR. The pulse duration, spatial mode, spectrum, and energy stability of the sidebands indicated that they were good enough for various multicolor femtosecond laser experiments. As many as 15 spectral upshifted pulses and 2 spectral downshifted pulses were obtained with a spectral bandwidth broader than 1.8 octaves.

Abstract: Î�ulticolor femtosecond pulses were simultaneously obtained by a cascaded FWM process in fused silica glass. The sideband spectra were tunable by changing the crossing angle of the two input beams. Frequency up-shift and down-shift pulses with energies as high as 1 Î¼J, durations of 45 fs, nearly diffraction limited Gaussian spatial profiles, and power stability smaller than 2% RMS of the generated sidebands were obtained. These multicolor sidebands can be used in various experiments, such as multicolor pump-probe experiment.

Abstract: Broadband 2-D multicolored arrays with more than ten periodic columns and more than ten rows were generated in a sapphire plate using two crossed femtosecond laser beams overlapping in time and space. These multicolored 2-D arrays were sensitive to rotation of the sapphire plate in the plane normal to the incident beams. The broadband spectrum, pulse duration less than 40fs, and less than 1%RMS power stability of the array signals make them well suited for various applications, for example multicolor pump-probe experiments.


Journal articles

2009	DOI Jun Liu, Takayoshi Kobayashi (2009) Wavelength-tunable multicolored femtosecond laser pulse generation in fused silica glass Opt. Lett. 34: 7. 1066-1068 April Abstract: Wavelength-tunable multicolored femtosecond laser pulses were generated simultaneously through cascade four-wave mixing in a fused-silica glass plate using two crossing femtosecond laser beams. The wavelength of the sidebands can be continuously tuned from UV to IR. The pulse duration, spatial mode, spectrum, and energy stability of the sidebands indicated that they were good enough for various multicolor femtosecond laser experiments. As many as 15 spectral upshifted pulses and 2 spectral downshifted pulses were obtained with a spectral bandwidth broader than 1.8 octaves. Notes:
	DOI Jun Liu, Takayoshi Kobayashi (2009) Generation of uJ multicolor femtosecond laser pulses using cascaded four-wave mixing Opt. Express 17: 7. 4984-4990 March Abstract: Î�ulticolor femtosecond pulses were simultaneously obtained by a cascaded FWM process in fused silica glass. The sideband spectra were tunable by changing the crossing angle of the two input beams. Frequency up-shift and down-shift pulses with energies as high as 1 Î¼J, durations of 45 fs, nearly diffraction limited Gaussian spatial profiles, and power stability smaller than 2% RMS of the generated sidebands were obtained. These multicolor sidebands can be used in various experiments, such as multicolor pump-probe experiment. Notes:
	Jun Liu, Takayoshi Kobayashi (2009) Generation of sub-20-fs multicolor laser pulses using cascaded four-wave mixing with chirped incident pulses Opt. Lett. 34: 16. 2402-2404 August Abstract: Notes:
	DOI Jun Liu, Takayoshi Kobayashi, Zhiguang Wang (2009) Generation of broadband two-dimensional multicolored arrays in a sapphire plate Optics Express 17: 11. 9226 May Abstract: Broadband 2-D multicolored arrays with more than ten periodic columns and more than ten rows were generated in a sapphire plate using two crossed femtosecond laser beams overlapping in time and space. These multicolored 2-D arrays were sensitive to rotation of the sapphire plate in the plane normal to the incident beams. The broadband spectrum, pulse duration less than 40fs, and less than 1%RMS power stability of the array signals make them well suited for various applications, for example multicolor pump-probe experiments. Notes:
2008	DOI Jun Liu, Jun Zhang, Takayoshi Kobayashi (2008) Broadband coherent anti-Stokes Raman scattering light generation in BBO crystal by using two crossing femtosecond laser pulses Optics Letter 33: 13. 1494 July Abstract: As broad as 12000 cmâ��1 coherent anti-Stokes Raman scattering (CARS) light from ultraviolet to infrared was generated in a BBO crystal by using two crossing femtosecond laser pulses with 30% conversion efficiency. More than fifteenth-order anti-Stokes and second-order Stokes Raman sidebands were observed with nice Gaussian spatial mode. The effect of the crossing angle between two input beams on the spectrum and emitting angle of the Raman sidebands was studied in detail. Calculation shows that the phase-matching condition determines the frequencies and angles of the sidebands. Notes:

	DOI J Liu, X W Chen, R X Li, T Kobayashi (2008) Polarization-dependent pulse compression in an argon-filled cell through filamentation Laser Physics Letter 5: 1. 45 January Abstract: Pulse compression through filamentation in an argonfilled cell was experimentally demonstrated by using circularly and linearly polarized pulses. A 53 fs circularly polarized pulse was successfully compressed to 15 fs. By using circularly polarized pulse input, the broadened spectrum was much wider and the incident energy in the gas cell can be increased by more than 3/2 times. Much shorter pulse could be compressed by using circularly polarized pulse input. Notes:
	DOI Jun Liu, Takayoshi Kobayashi (2008) Cascaded four-wave mixing and multicolored arrays generation in a sapphire plate by using two crossing beams of femtosecond laser Optics Express 16: 26. 22119 December Abstract: Ultrabroadband signals were found to be generated by cascaded four-wave mixing in a bulk medium by using two crossing femtosecond laser pulses. As many as fifteen spectral upshifted pulses and two spectral downshifted pulses were obtained with spectral bandwidth broader than 1.5 octaves. Bright upshifted pulses were observed on both sides of the two crossing beams. Two dimensional multicolored arrays were observed for the first time in a sapphire plate medium. Notes:
2007	Jun Liu, Xiaofang Li, Xiaowei Chen, Yongliang Jiang, Ruxin Li, Zhizhan Xu (2007) 1-kHz high efficiency Ti:sapphire laser amplifier Chinese Optics Letters 5: S1. S163-S165 May Abstract: Notes:
	Liu Jun, Li Xiaofang, Chen Xiaowei, Jiang Yongliang, Li Ruxin, Xu Zhizhan (2007) 1kHz-0.1TW high efficiency Ti:sapphire laser amplifier Acta Phys. Sin. 56: 3. 1375-1378 March Abstract: Notes:
	DOI Xiaowei Chen, Xiaofang Li, Jun Liu, Pengfei Wei, Xiaochun Ge, Ruxin Li, Zhizhan Xu (2007) Generation of 5 fs, 0.7 mJ pulses at 1 kHz through cascade filamentation Optics Letter 32: 16. 2402 August Abstract: Two-cycle optical pulses with duration of 5 fs and energy of 0.7 mJ have been generated at 1 kHz by compressing the 38 fs laser pulses from a carrier-envelope phase (CEP) controlled Ti:sapphire laser system through a cascade filamentation compression technique. A simple and effective method is developed to suppress multiple filament formation and stabilize a single filament by inserting a soft aperture with an appropriate diameter into the driving laser beam prior to focusing, resulting in an excellent compressed beam quality. The good beam quality and potentially higher peak power make this ultrashort laser pulse source a significant tool for high-field physics applications. Notes:
2006	Jun Liu, Xiaowei Chen, Jiansheng Liu, Yuxin Leng, Yi Zhu, Jun Dai, Ruxin Li, Zhizhan Xu (2006) Properties of the propagation of negatively chirped femtosecond pulses in normally dispersive media Acta Phys. Sin. 55: 4. 1821-1826 April Abstract: Notes:
	Liu Jun, Chen Xiaowei, Zhu Yi, Leng Yuxin, Dai Jun, Ge Xiaochun, Li Ruxin, Xu Zhizhan (2006) Compression of intense laser pulse through filamentaion in an argon-filled cell Chin. Phys. Lett. 23: 2. 374-376 February Abstract: Notes:
	DOI Jun Liu, Xiaowei Chen, Jiansheng Liu, Yi Zhu, Yuxin Leng, Jun Dai, Ruxin Li, Zhizhan Xu (2006) Spectrum reshaping and pulse self-compression in normally dispersive media with negatively chirped femtosecond pulses Optics Express 14: 2. 979-987 January Abstract: The spectral and the temporal behavior of high-intensity negatively chirped femtosecond pulses in normally dispersive media at different input parameters are experimentally studied. The spectrum of the pulse is reshaped due to strong self-actions. The pulse is self-compressed, instead of broadening, accompanied with the spectral FWHM bandwidth shortened. Steepening of the leading edge of the pulse and spectral red-shift are observed in the experiment. The numerical simulation shows that the result is in agreement with the experimental result. Notes:
	Chen Xiaowei, Jiang Yongliang, Leng Yuxin, Liu Jun, Ge Xiaochun, Li Ruxin, Xu Zhizhan (2006) Pulse compression through filamentation in argon with AOPDF for pre-dispersion compression Chin. Phys. Lett. 23: 5. 1198-1200 May Abstract: Notes:
	Li Xiaofang, Chen Xiaowei, Jiang Yongliang, Liu Jun, Zeng Zhinan, Li Ruxin, Xu Zhizhan (2006) High-power extracavity pulse compression in solid material Chin.Phys.Lett. 23: 12. 3278-3280 December Abstract: Notes:
	DOI Xiaowei Chen, Yuxin Leng, Jun Liu, Yi Zhu, Ruxin Li, Zhizhan Xu (2006) Pulse self-compression in normally dispersive bulk media Optics Communications 259: 1. 331-335 March Abstract: We experimentally demonstrate that high-power femtosecond pulses can be compressed during the nonlinear propagation in the normally dispersive solid bulk medium. The self-compression behavior was detailedly investigated under a variety of experimental conditions, and the temporal and spectral characteristics of resulted pulses were found to be significantly affected by the input pulse intensity, with higher intensity corresponding to shorter compressed pulses. By passing through a piece of BK7 glass, a self-compression from 50 to 20 fs was achieved, with a compression factor of about 2.5. However, the output pulse was observed to be split into two peaks when the input intensity is high enough to generate supercontinuum and conical emission. Notes:
2005	Xiaowei Chen, Yi Zhu, Jun Liu, Yuxin Leng, Ge Xiaochun, Ruxin Li, Zhizhan Xu (2005) Self-compression of femtosecond laser pulses in normally dispersive solid material. Acta Phys. Sin. 54: 11. 5178 November Abstract: Notes:
	Xiaowei Chen, Jun Liu, Yi Zhu, Yuxin Leng, Ge Xiaochun, Ruxin Li, Zhizhan Xu (2005) Self-compression of high-intensity femtosecond laser pulses in air Acta Phys. Sin. 54: 8. 3665-3669 August Abstract: Notes:
Book chapters

2006	Ruxin Li, Xiaowei Chen, Jun Liu, Yuxin Leng, Yi Zhu, Xiaochun Ge, Haihe Lu, Lihuang Lin, Zhizhan Xu (2006) Pulse Self-Compression in the Nonlinear Propagation of Intense Femtosecond Laser Pulse in Normally Dispersive Solids In: Progress in Ultrafast Intense Laser Science I 259-273 Springer, Germany Abstract: Notes:
Conference papers

2007	Xiaowei Chen, Xiaofang Li, Jun Liu, Pengfei Wei, Ruxin Li, Zhizhan Xu (2007) Generation of 5fs, 0.7mJ two-cycle pulses at 1kHz with CEP controlled through cascade filamentation. In: CLEO/QELS 2007 CMDD1 Abstract: Notes:
2006	Liu Jun, Li Xiaofang, Chen Xiaowei, Jiang Yongliang, Li Ruxin, Xu Zhizhan (2006) 1kHz high efficiency Ti:sapphire laser amplifier In: APLS 2006 Abstract: Notes:
2005	Ruxin Li, Xiaowei Chen, Jun Liu, Yuxin Leng, Yi Zhu, Xiaochun Ge, Haihe Lu, Lihuang Lin, Zhizhan Xu (2005) Extremely short pulse compression in bulk materials: a scheme for generating few cycle intense laser pulses In: Proc. Of SPIE2005 102-111 Abstract: Notes:
	DOI Jun Liu, Xiaowei Chen, Zhu Yi, Ruxin Li, Zhizhan Xu (2005) pulse self-compression in normally dispersive media with negatively chirped femtosecond pulses In: CLEO/QELS 2005 1842- 1844 vol. 3 Abstract: Notes:

Journal articles

Book chapters

Conference papers