Continuously variable, electrically addressed beam splitter based on vanadium dioxide

Vanadium dioxide (VO2) is used to implement an electrically addressable beam splitter with continuously variable splitting ratios. The electrical control of temperature in a thin VO2 layer is used to vary its transmission/reflection behavior. The technique is characterized for various incidence angles, s- and p-polarizations, and the wavelength range of 400–2000 nm. Splitting ratios continuously tunable over four orders of magnitude are reported.