The minimization of laser diode relative intensity noise (RIN) is an important consideration for obtaining the optimum system performance in many optical communications systems. RIN is a catch-all term that defines the laser's noise floor which results in increased system noise figure and limited dynamic range. This paper is a tutorial on RIN, explaining what it is, how it can be measured, and what can be done to alleviate it. The laser structure parameters and dynamic processes which affect RIN and the methodology to reduce the RIN of an existing laser will be addressed. The general characteristics of a low-noise semiconductor laser diode, best exemplified by a multiple quantum well laser are also discussed in detail.
"Minimization Of Laser Diode Relative Intensity Noise (RIN)", Proc. SPIE 1044, Optomechanical Design of Laser Transmitters and Receivers, (11 July 1989); doi: 10.1117/12.951301; https://doi.org/10.1117/12.951301