|Abstract: ||A time-resolved microwave reflectance apparatus comprises a pulsed or
modulated optical source that irradiates a semiconductor sample with an
excitation pump beam, a microwave oscillator that irradiates the sample
with a continuous beam of microwaves, and a microwave detector that
detects the microwaves reflected by the sample. Therefore, charge
detection, rather than conventional absorption measurements (that detect
the loss of photons), can be used to extract the absorption coefficient
and band edge of a semiconductor material.