Tailoring Chirp in Spin-Lasers

TL;DR

This paper explores methods to control and reduce chirp in spin-lasers, which are semiconductor lasers with spin-polarized carriers, aiming to improve their modulation performance and bandwidth.

Contribution

It provides a generalized expression for chirp in spin-lasers and proposes modulation schemes to eliminate chirp and enhance bandwidth.

Findings

Chirp can be tailored in spin-lasers through specific modulation schemes.

Proposed methods can simultaneously eliminate chirp and increase bandwidth.

The generalized chirp expression aids in designing better spin-laser modulation strategies.

Abstract

The usefulness of semiconductor lasers is often limited by the undesired frequency modulation, or chirp, a direct consequence of the intensity modulation and carrier dependence of the refractive index in the gain medium. In spin-lasers, realized by injecting, optically or electrically, spin-polarized carriers, we elucidate paths to tailoring chirp. We provide a generalized expression for chirp in spin-lasers and introduce modulation schemes that could simultaneously eliminate chirp and enhance the bandwidth, as compared to the conventional (spin-unpolarized) lasers.