Modeling quantum dot lasers with optical feedback: sensitivity of bifurcation scenarios

• Published in: Physica status solidi. B. Basic research Vol. 247; no. 4; pp. 829 - 845
• Main Authors: Otto, Christian, Lüdge, Kathy, Schöll, Eckehard
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Berlin WILEY-VCH Verlag 01.04.2010; WILEY‐VCH Verlag; Wiley-VCH
• Subjects: 42.55.Px; 42.55.Px, 42.60.Da, 85.35.Be; 42.60.Da; 85.35.Be; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Lasers; Nonlinear optics; Optical bistability, multistability and switching, including local field effects; Optics; Physics; Semiconductor lasers; laser diodes; Quantum dot lasers; Optical confinement; Semiconductor lasers; Optical feedback; Feedback; Quantum dots; Quantum wells; Rate equation; Quantum well lasers; Optical multistability; External cavity; Electric fields
• ISSN: 0370-1972; 1521-3951
• DOI: 10.1002/pssb.200945434

We present a systematic study of the complex dynamics of a quantum dot (QD) laser subjected to optical feedback from a short external cavity. Our model consists of a Lang–Kobayashi like model for the electric field combined with a microscopically based rate equation system. We separately treat electron and hole dynamics in the QDs and the surrounding wetting layer (WL). By tuning the phase–amplitude coupling and the optical confinement factor we are able to discuss various scenarios of the dynamics on the route towards conventional quantum well (QW) lasers. Due to the optical feedback, multistability occurs in our model in form of external cavity modes (ECMs) or delay‐induced intensity pulsations. In dependence of the feedback strength we analyze complex bifurcation scenarios for the intensity of the emitted laser light as well as time series, power spectra, and phase portraits of all dynamic variables in order to elucidate the internal dynamics of the laser. Quantum dot (QD) lasers are promising devices for future telecommunication applications due to their higher tolerance to optical feedback in comparison to quantum well (QW) lasers. In this work a systematic study of the complex dynamics of a QD laser subjected to optical feedback from a short external cavity is presented. The QD model consists of a Lang‐Kobayashi‐like equation for the electric field combined with a system of microscopically based rate equations for the carriers. The dynamics of electrons and holes in the QDs and the surrounding wetting layer are separately treated. Due to the optical feedback, multistability occurs in our model in form of external cavity modes (ECMs) or delay‐induced intensity pulsations.