Mj. Snelling et al., ELECTROOPTIC POLARIZATION MODULATION IN [110]-ORIENTED GAAS-INGAAS MULTIPLE-QUANTUM WELLS, IEEE journal of quantum electronics, 33(7), 1997, pp. 1114-1122
An electrooptic modulator that is sensitive to the polarization state
of transmitted light is demonstrated by using the intrinsic optical an
isotropy of biaxially strained [110]-oriented GaAs-InxGa1-xAs multiple
quantum wells, The ellipticity and the direction of polarization of a
linearly polarized input pulse are modulated by a change in the in-pl
ane dichroism and birefringence produced by a change in the voltage ap
plied across the p-i-n region containing the quantum wells, Sensitive
ellipsometric measurements are used to directly measure the anisotropy
in the complex index of refraction between the two principal inplane
axes of the sample as a function of wavelength for selected voltages,
The latter information is then used to determine the operating wavelen
gth, the contrast ratio, the optical bandwidth, and the tunability of
the modulator, This structure requires only standard elementary post-g
rowth processing.