We investigate the possibility of concealing the time-delay signatures in semiconductor ring lasers (SRLs) with external feedback. Through the autocorrelation and delayed mutual information, we report different scenarios leading to simultaneous time-delay concealment both in the intensity and the phase dynamics of such systems. In particular, the fact that such delay signatures can be eliminated in a SRL subject to short feedback constitutes a step toward the possibility of implementing secure communication schemes and random number generators on chip.
© 2012 Optical Society of America
Original Manuscript: March 14, 2012
Revised Manuscript: April 27, 2012
Manuscript Accepted: May 6, 2012
Published: June 21, 2012
Romain Modeste Nguimdo, Guy Verschaffelt, Jan Danckaert, and Guy Van der Sande, "Loss of time-delay signature in chaotic semiconductor ring lasers," Opt. Lett. 37, 2541-2543 (2012)