Laser Safety, 2nd Edition

22Tunable External Cavity Diode Lasers

Diana Warren

Introduction

Tunable external cavity diode lasers (ECDLs) are useful in many applications, including atomic and molecular laser spectroscopy, laser cooling, atomic clocks, environmental sensing, phase-shifting interferometry, coherent optical telecommunications, and exciting new fields such as optical microresonators and quantum computing. Aside from tunability, these applications require continuous-wave, single-mode, and narrow-linewidth laser sources. Semiconductor diode lasers are attractive because of their low cost, although not an ideal choice since they typically operate with several longitudinal modes lasing simultaneously, leading to low coherence and therefore large linewidths. However, ...