Interferometric ellipsometer with wavelength-modulated laser diode source.
An interferometric ellipsometer, with no moving parts and an inexpensive laser diode source, is demonstrated. Temporal fringes are produced by a small modulation of the laser diode bias current and unbalanced arms in the interferometer. Fringe analysis algorithms are developed, and accurate measurements of the optical properties of a number of samples are made. Temperature tuning the laser diode center wavelength allows the frequency dependence of the optical properties to be determined over a wavelength range of approximately 1 nm.
Watkins
Lionel R
LR
Department of Physics, University of Auckland, Private Bag, Auckland, New Zealand. l.watkins@auckland.ac.nz
Hoogerland
Maarten D
MD