Numerical Investigation on Feedback Insensitivity in Semiconductor Nanolasers (original) (raw)
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Physics and Simulation of Optoelectronic Devices XIX, 2011
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Thesis the University of Arizona Source Dai B 61 02 P 917 Aug 2000 112 Pages, 1999
Introduction 19 2.2 Quantum mechanics of spontaneous emission rate 2.3 Introduction to the guided waves for slab wave guides 27 3 EXPERIMENTS ON CONTROLLED SPONTANEOUS EMISSION IN SEMICONDUCTOR MICROCAVITIES 37 3.1 Introduction 37 3.2 Experimental setup and sample structures 40 3.3 Experimental results and discussion 50 3.4 PL angular distribution and quantum efficiency measurements S3 3.5 The comparison with the theoretical calculation 3.6 Conclusion 3.11 Electron-hole recombination rate as a fiinction of the number of layers in the top mirror of Yokoyama et al. [26], showing very little cavity-QED enhancement 61 4.1 Energy level diagrams for the coupled system of atoms and photons in a cavity for (a) Single-atom case and (b) m-atom case 4.2 A cavity consisting of two planar mirrors. The optical susceptibility Xres((o) of Lorentz oscillators leads to refractive index n((a) and absorption a(a)) of the medium 71 4.3 Absorption coefficient (a) and refractive index (b) of a Lorentz oscillator 72 4.4 Graphical solution for the peak positions of a Fabry-Perot resonator (a) for a constant refractive index nb, and (b) for a Lorentz oscillator index n(A«) 4.5 Numerically calculated reflection, transmission and absorption curves of a Fabry-Perot resonator containing Lorentz oscillators 76 5.1 Experimental setup for linear and cw nonlinear measurements ofNMC 80 5.2 Absorption spectrum ofNMC21 at lOK 5.3 (a) Reflection spectra from sample NMC22 as the cavity is tuned from higher to lower energy through the exciton resonance. Corresponding anti-crossing diagram as a function of position on the sample 84 5.4 Reflection and Transmission spectra at minimum splitting of NMC22. Two peaks are quite asymmetric in both amplitude and linewidth, in contrast to the prediction by the theory of symmetric optical susceptibility 85
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We report on a general theory describing the effect of external optical feedback on the steady-state noise characteristics of single-mode semiconductor lasers. The theory is valid for arbitrarily strong feedback and arbitrary optical feedback configuration and spectrum. A generalized Langevin rate equation is derived. The equation is, in general, infinite order in d / d t constituting an infinite-order correction to the low-frequency weak-feedback analysis. The general formalism includes relaxation oscillations, and allows us to analyze the effect of feedback on both the laser linewidth, frequency noise, relative intensity noise, and the relaxation oscillation sidebands in the field spectrum. The theory is applied to two important feedback configurations; the laser coupled to a single mirror and the laser coupled to a high-Q cavity. The analysis includes excess low-frequency noise due to temperature fluctuations in the laser chip. . His current research interests include spectral and dynamic properties of semiconductor lasers, ultrafast optics, and electrooptic sampling.