Observation of spectral modulation coupled with broadband transverse-mode-locking in an Yb:CALGO frequency-degenerate cavity  

作　　者：Yijie Shen Zhensong Wan Xing Fu Mali Gong 申艺杰;万震松;付星;巩马理(State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University)

机构地区：[1]State Key Laboratory of Precision Measurement Technology and Instruments, Department of Precision Instrument, Tsinghua University

出　　处：《Chinese Optics Letters》2019年第3期60-65,共6页中国光学快报（英文版）

基　　金：funded by the National Key Research and Development Program of China(No.2017YFB1104500);the Natural Science Foundation of Beijing Municipality(No.4172030);and the Beijing Young Talents Support Project(No.2017000020124G044)

摘　　要：A frequency-degenerate cavity(FDC) is the resonator that the ratio of transverse and longitudinal mode frequency spacings is a simple rational number. When an optical resonator is close to the FDC, transverse-mode-locking(TML) takes place with drastic changes of laser mode. We report for the first time, to the best of our knowledge,the multi-frequency emission and spectral modulation effects coupled with TML in FDC. The Yb:CaGdAlO_4(Yb:CALGO) crystal with large gain bandwidth was used as a gain medium in an off-axis-pumped hemispherical FDC for realizing broadband emission. Interestingly, the spectrum can transform from a single smooth packet shape to a multi-peak structure; meanwhile, the transverse pattern accordingly transforms into some exotic wave-packet profiles through controlling off-axis displacement in a special degenerate state.A frequency-degenerate cavity(FDC) is the resonator that the ratio of transverse and longitudinal mode frequency spacings is a simple rational number. When an optical resonator is close to the FDC, transverse-mode-locking(TML) takes place with drastic changes of laser mode. We report for the first time, to the best of our knowledge,the multi-frequency emission and spectral modulation effects coupled with TML in FDC. The Yb:CaGdAlO_4(Yb:CALGO) crystal with large gain bandwidth was used as a gain medium in an off-axis-pumped hemispherical FDC for realizing broadband emission. Interestingly, the spectrum can transform from a single smooth packet shape to a multi-peak structure; meanwhile, the transverse pattern accordingly transforms into some exotic wave-packet profiles through controlling off-axis displacement in a special degenerate state.

关 键 词：OBSERVATION SPECTRAL MODULATION frequency-degenerate CAVITY 

分 类 号：O3[理学—力学]