Novel use of diamond in eye-safe lasers

Rights statement
Awarding institution
  • University of Strathclyde
Date of award
  • 2020
Thesis identifier
  • T15561
Person Identifier (Local)
  • 201651413
Qualification Level
Qualification Name
Department, School or Faculty
  • The phenomenon of stimulated Raman scattering is one of the ways of accessing a laser emission spectrum. This thesis focuses on converting a 1µm laser to the so called eye-safe 1.5µm wavelength useful in e.g. LIDAR applications. The novelty of this approach is that compared to ion based lasers e.g. Er:fiber, Raman lasers are mostly limited by the pump power, not by the thermal roll off, especially when using materials such as diamond with extremely high thermal conductivity. This is subjected to the absorption in the Raman crystal and other effects described more in detail in the introduction. The work presents firstly a design of a proof of concept, low power and repetition rate pump source at 1µm based on Nd:YAG and a an external cavity Raman diamond laser. This laser was investigated to find the optimum operating conditions such as pump intensity, output coupling transmission and a laser cavity mode size. These findings were then applied in high average power Diamond Raman laser. These experiments used an Yb based fiber master oscillator, power amplifier which acted as a pump source. These experiments concluded with obtaining over 10W of average power at 150kHz of laser emission above 1.5µm wavelength. This method of generating eye-safe wavelengths is a promising way to high power and repetition rate emission. A novel approach of generating high average power especially with a narrow linewidth emission is also presented by using a Raman cavity in an amplifier configuration. A first diamond based, second Stokes Raman amplifier operating at eye-safe wavelengths regime is presented in Chapter 5.
Advisor / supervisor
  • Savitski, Vasili
  • Kemp, Alan
Resource Type
  • This thesis was previously held under moratorium from 9th October 2020 to 9th October 2022.
Date Created
  • 2020
Former identifier
  • 9912922493402996