Optical phase transitions in bilayer semiconductor hyperbolic metamaterials

We have been studied optical response of the semiconductor hyperbolic metamaterials (HMM) based on bilayer InGaAs/GaSb compound. It reveals that analytically derived profile of the photonic density of states is reminiscent of Fermi electronic band structure of metal or semiconductors. Similar to the electronic systems where chemical potential plays a key role in electronic Lifshitz type phase transitions, the photonic Fermi surface experiences instabilities induced by the changes in volume fractions of its constituents that leads to the Lifshitz type photonic phase transitions between dielectric phase and types I and II hyperbolic states at critical points.