Related Experiment Video
Updated: Jun 11, 2026
Construction and Characterization of External Cavity Diode Lasers for Atomic Physics
Published on: April 24, 2014
Wide-tuning-range Littman-type external-cavity diode laser for spectroscopy of GaAs band-edge and impurity-level
Abstract:
We report the design and implementation of a compact external-cavity diode laser (ECDL) for wavelength-tunable excitation around the GaAs bandgap. By modifying a commercial laser kit and redesigning key optomechanics, we achieve wide wavelength tunability over 790-870 nm. We describe a geometrical-optics design procedure that accounts for the tuning-mirror pivot constraint, together with practical assembly and interference-mitigation measures for wavelength-scanned operation. The ECDL operates in a single longitudinal mode with a linewidth below several tens of MHz (measurement-limited) and delivers an optical output power of tens of mW across the tuning range. Free-running frequency drifts are on the order of 50 MHz over tens of seconds and 500 MHz over tens of minutes without active feedback.
Related Concept Videos
01:26Inductively Coupled Plasma Atomic Emission Spectroscopy: Instrumentation
There are three main types of inductively coupled plasma atomic emission spectroscopy (ICP-AES) instruments: sequential, simultaneous multichannel, and Fourier transform instruments, with the latter being less commonly used.
01:26Raman Spectroscopy Instrumentation: Overview
The monochromatic laser source, typically using visible or near-infrared radiation, generates a highly focused beam of light. This light interacts with the molecules of the sample, scattering some of the light. Liquid and gaseous samples are usually tested in ordinary glass capillaries, while solids can be analyzed as powders packed in capillaries or as potassium...