Suchergebnisse

We implement a method to identify the deterministic nature of specific events in the dynamics of a semiconductor laser subject to time-delayed optical feedback. Specifically, we study the power dropouts in the low-frequency fluctuations regime on an individual event basis and identify whether the underlying dominant mechanism is deterministic. Our approach is based on sychronization with a twin system in a symmetric relay configuration. We investigate the dependence of the fraction of deterministically driven (i.e., synchronized) dropouts on the laser's pump current as a key parameter. Our experimental results are corroborated by numerical modeling based on rate equations. Our numerical findings also provide insights into the influence of spontaneous emission noise. © 2013 American Physical Society. ; This work was supported by MICINN (Spain) under Project TEC2009-14101 (DeCoDicA), by MINECO (Spain) under Project TEC2012-36335 (TRIPHOP), by the Government of the Balearic Islands within Grups Competitius, and by the European Commission under EC FP7 Project PHOCUS (Grant No. 240763). K.H. acknowledges financial support from the Government of the Balearic Islands (Department of Education, Culture, and Universities), cofunded by the European Social Fund. ; Peer Reviewed

We investigate the dynamics of semiconductor lasers subject to time-delayed optical feedback from the perspective of dynamical self-injection locking. Based on the Lang-Kobayashi model, we perform an analysis of the well-known Low Frequency Fluctuations (LFFs) in the frequency-intensity plane. Moreover, we investigate a recently found dynamical regime of fragmented LFFs by means of a locking-range analysis, spectral comparison and precursor pulse identification. We show that LFF dynamics can be explained by dynamical optical injection locking due to the delayed optical feedback. Moreover, the fragmented LFFs occur due to a re-injection locking induced by a particular optical pulse structure in the chaotic feedback dynamics. This is corroborated by experiments with a semiconductor laser experiencing delayed feedback from an optical fiber loop. The dynamical nature of the feedback injection results in an eventual loss, but also possible regaining, of the locking, explaining the recently observed phenomenon of fragmented LFFs. ; This work was supported by the Spanish Ministerio de Economía, Industria y Competitividad (MINECO), under project Nos. TEC2012–36335, FIS2015–71929-REDT, and TEC2016–80063-C3 (AEI/FEDER, UE). K.H. acknowledges financial support from the Government of the Balearic Islands (Department of Education, Culture, and Universities), co-funded by the European Social Fund. M.C.S. was supported by MINECO through a Ramón y Cajal Fellowship (RYC-2015–18140). D.B. acknowledges support of the CNRS under project No. PICS07300. ; Peer reviewed