Theoretical Modeling of Relative Intensity Noise in p-Doped 1.3-μm InAs/GaAs Quantum Dot Lasers

Abstract

Theoretical analysis of relative intensity noise (RIN) characteristics of p-doped QD lasers has been presented. By considering dynamics of electrons and holes separately at GaAs barrier, wetting layer (WL), and three discrete QDs levels, twelve rate equations have been linearized in presence of Langevin noise sources. Calculations indicate that RIN level of QD laser reduces slightly through p-doping. Although providing excess holes to WL state decreases shot noise resulted from quantum confined levels and photon noise, the shot noise originated from three and two dimensional carrier densities, respectively inside the barrier and WL states, increases. It is shown that the RIN level declines in pdoped QD lasers by increasing the injection current which is in agreement with a recent experimental report. It is also demonstrated that the RIN level of QD lasers decreases by increasing the number of QD layers and shot noise plays the main role in this reduction.

RIN in Gain-Switched Dual-State Lasing Quantum Dot Lasers Based on Multi-population Rate Equations

“…For both GaAs and InP based Q-Dot lasers RIN was measured approximately -160 dB/Hz, whereas RIN level was found approximately -120 dB/Hz and -150 dB/Hz for Q-Dot lasers grown on Ge and Si substrates [9][10][11][12]. A little RIN reduction through the p-doping for InAs-GaAs Q-Dot lasers was demonstrated theoretically by Sanee et.al [13]. It was also shown that RIN of Q-Dot laser due to Exs radiation is more suppressed than that of the Grs [14].…”

“…al reported that carrier noise originated from excited state and ground state of Q-Dot lasers increase the RIN of Q-Dot lasers, whereas enhancing energy difference between the ground state and the excited state reduce carrier noise contribution from the excited state [15]. As a result, there have been some papers investigating RIN of Q-Dot lasers for InGaAs-GaAs and InAs-InP [9][10][11][13][14][15][16][17][18][19][20][21]. However, most of them are not enough to clearly explain the RIN spectrum of Q-Dot lasers.…”

“…However, most of them are not enough to clearly explain the RIN spectrum of Q-Dot lasers. Because, they investigated only noise of single-mode model (SM) [13,15,19], or didn't consider carrier noise [18], or only took into consideration of wetting layer carrier noise [20], or demonstrated dual-state lasing for single-mode model (SM) [21]. Therefore, here for the first time, comprehensive RIN analysis of the gain-switched InAs-InP dual-state lasing Q-Dot laser for multi-mode model (MM) considering nonlinear gain was examined.…”

Enhanced Modulation and Noise Characteristics in 1.55 µm QD Lasers using Additional Optical Pumping

“…Such measurements yield the noise spectrum regarded to the laser output power. Thus, the intensity noise is characterized by the relative intensity noise per unit bandwidth as following [24]:…”

Frequency noise analysis of 1.55 µm indium arsenide/indium phosphide quantum dot lasers: impact of non‐linear gain and direct carrier transition

“…Moreover, randomness of spontaneous emissions also results in phase and frequency fluctuations. Though many experimental [16, 18] and theoretical [17, 19] efforts have been devoted to study various operational characteristics of QD lasers so far, less can be found about the noise properties of these novel lasers in the literatures [23, 25] because of further technical and mathematical complications. To the best of our knowledge, no work has been reported about FN of QD lasers neither experimentally nor theoretically, till now.…”