Relative intensity noise reduction in a dual-state quantum-dot laser by optical feedback

Abstract

We report a reduction of the relative intensity noise (RIN) in a dual-state emitting quantum-dot laser subject to the state-selective optical feedback on the ground state and excited state. Numerically, we map the evolution of the RIN for variations of the optical feedback phases for both states. We report important differences in the impact of the feedback when applied to the ground or excited state, and observe regimes for which a significant reduction in RIN is achieved. Experimentally, we confirm these results and achieve a 16 dB reduction of the RIN via a careful and independent tuning of the optical feedback phase for each state.

Time Delay Signature Suppression in Semiconductor Laser with Double Optical Feedback

“…In short, even when working with the laser in a stable state, a small subwavelength change of the mirror position can impact the lasing properties. It is interesting here to notice the analogy with the case of a two-state emitting quantum dot laser but with a single optical feedback loop 30 . Similar patterns are observed as each emitting mode experiences a different feedback phase due to the wavelength difference, hence leading to a synthetic dual-feedback configuration.…”

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

“…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.…”

Compact Dual-Wavelength Lasers on InP Generic Foundry Platform

“…The simplest way is to combine the beams of two separate semiconductor laser sources, which usually results in bulky setups and poses a challenge to stabilize mechanically. Although this allows for a great flexibility in spectral tuning and the precise control of their optical power, semiconductor lasers with intrinsic multiwavelength selection like edge-emitting quantum-dot lasers can emit from the ground and excited state at the same time, yet usually require asymmetrical biasing [5], low temperatures [6] or embedded gratings [7] to achieve a dual-wavelength emission. External optical grating feedback adds an additional degree of emission control to extend their operation range [8] [9], but demands high mechanical and thermal stability.…”