title: Generation and spectral manipulation of coherent terahertz radiation with two-stage optical rectification.
abstract: We propose and experimentally demonstrate the generation of single-cycle terahertz radiation with two-stage optical rectification in GaSe crystals. By adjusting the time delay between the pump pulses employed to excite the two stages, the terahertz radiation from the second GaSe crystal can constructively superpose with the terahertz field injected from the first stage. The high mutual coherence between the two terahertz radiation fields is ensured with the coherent optical rectification process and can be further used to synthesize a desired spectral profile of coherent THz radiation. The technique is also potentially useful for generating high-power single-cycle terahertz pulses, usually limited by the pulse walk-off effect of the nonlinear optical crystal used.
authors.affiliation: Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, Hsinchu, Taiwan 30010, ROC.
authors.forename: Ching-Wei
authors.initials: CW
authors.lastname: Chen
authors.forename: Yu-Shian
authors.initials: YS
authors.lastname: Lin
authors.forename: Jung Y
authors.initials: JY
authors.lastname: Huang
authors.forename: Chen-Shiung
authors.initials: CS
authors.lastname: Chang
authors.forename: Ci-Ling
authors.initials: CL
authors.lastname: Pan
authors.forename: Li
authors.initials: L
authors.lastname: Yan
authors.forename: Chao-Kuei
authors.initials: CK
authors.lastname: Lee
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005708:Gallium / Q000737:chemistry*; D007259:Infrared Rays; D007368:Interferometry / Q000295:instrumentation*; D008029:Lighting / Q000295:instrumentation*; D008872:Microwaves; D008962:Models, Theoretical; D012031:Refractometry / Q000295:instrumentation*; D012643:Selenium / Q000737:chemistry*
chemical_list: C517764:gallium selenide; D005708:Gallium; D012643:Selenium