Open AccessLarge magnitude, sign controllable, ultrafast group-velocity control via resonant cascaded nonlinearity in tandem
Author(s) -
Bingjie Zhou,
Jingui Ma,
Jing Wang,
Peng Yuan,
Guoqiang Xie,
Liejia Qian
Publication year - 2020
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.403447
Subject(s) - group delay and phase delay , ultrashort pulse , group velocity , physics , optics , sign (mathematics) , pulse duration , tandem , superposition principle , pulse (music) , laser , materials science , telecommunications , mathematics , bandwidth (computing) , computer science , quantum mechanics , mathematical analysis , detector , composite material
Resonant cascaded nonlinearity (RCN) induced by optical parametric amplification (OPA) in a chirped quasi-phase-matching chip can be applied to control the group velocity of ultrafast lasers. However, the group delay produced in a single-stage OPA is limited to the pulse duration, and its sign cannot be altered. In this study, we propose a tandem RCN configuration with multiple OPA stages that can produce large-magnitude and sign-controllable group delays. The group delay produced in the multi-stage configuration is shown to be a linear superposition of each single-stage group delay. By virtue of the byproduct idler in the OPA process, the signal-group delay can be altered from positive to negative (and vice versa) with the same chip structure and pump condition. In the numerical simulation with two OPA stages, both a positive and negative group delay of six-fold pulse duration were achieved for 100-fs pulses at 1550 nm. A much larger group delay can be achieved by increasing the number of OPA stages.