Measurement of the d(36) coefficient of mercury cadmium telluride by reflection second harmonic generation

The second order nonlinear coefficient (d36) of the narrow band gap semiconductor, mercury cadmium telluride (MCT), is measured. Because MCT is strongly absorbing at a 1.06 μm wavelength, the measurement was performed by comparing the second harmonic intensity reflected from the material surface to the second harmonic intensity measured for a quartz sample in transmission. The analysis depends on the derivation of comparable expressions for the reflected and transmitted intensities. Using this approach a value of d36=350±40 pm/V is obtained, a value much larger than those reported for similar zinc-blende type materials. The large magnitude of the MCT d36 is attributed to an electronic resonance enhancement