title: Enhanced optical precursors by Doppler effect via active Raman gain process.
abstract: A scheme for enhancing precursor pulse by Doppler effect is proposed in a room-temperature active-Raman-gain medium. Due to abnormal dispersion between two gain peaks, main fields are advanced and constructively interfere with optical precursors, which leads to enhancement of the transient pulse at the rise edge of the input. Moreover, after Doppler averaging, the abnormal dispersion intensifies and the constructive interference between precursors and main fields is much strengthened, which boosts the transient spike. Simulation results demonstrate that the peak intensity of precursors could be enhanced nearly 20 times larger than that of the input.
authors: Department of Applied Physics, College of Science, Shandong University of Science and Technology, Qingdao, Shandong 266590, China.
authors: Yandong
authors: Y
authors: Peng
authors: Yueping
authors: Y
authors: Niu
authors: Lida
authors: L
authors: Zhang
authors: Aihong
authors: A
authors: Yang
authors: Lin
authors: L
authors: Jiang
authors: Shangqing
authors: S
authors: Gong