Bispectral Optical Cavity based on Twin Metamirrors

Abstract

Metasurfaces, the two-dimensional variant of metamaterials, manipulate light in unique ways, opening up a whole new world of optical functionalities, ranging from optical imaging to quantum optics. High reflectivities and tailored phase profiles could allow such metamirrors to outperform conventional multilayer mirrors for high-precision optical interferometry due to their low thermal noise. Here, we design twin metamirrors with theoretical reflectivities of > 99.9 % at 1064 nm and 1550 nm. These mirrors can be implemented in bispectral low-noise optical cavities, which would reduce the number of cavities or can be used as a transfer cavity for quantum experiments like atomic clocks.