The nonlinear dynamics of lasers with frequency-shifted delayed feedback are investigated. Resonant excitation of sustained relaxation oscillations by harmonic resonance is demonstrated. Self-induced switching between sustained relaxation oscillation and spiking oscillation is observed as the feedback coefficient is increased. Observed instabilities are well reproduced by numerical simulations of proposed model equations. A statistical analysis of this switching phenomenon is carried out numerically, and the results indicate that an inverse-power relation with the feedback coefficient determines the periods over which the system dwells in its relaxation-oscillation state.
© 2001 Optical Society of America
Kenju Otsuka, Jing-Yuan Ko, and Tamaki Kubota, "Nonstationary chaotic oscillations in lasers with frequency-shifted feedback," Opt. Lett. 26, 638-640 (2001)