Steinlechner, Fabian OliverFabian OliverSteinlechnerMarques Muniz, André LuizAndré LuizMarques MunizFlügel-Paul, ThomasThomasFlügel-Paul2023-12-052023-12-052023-06-14https://publica.fraunhofer.de/handle/publica/457583It is claimed a polarization analysis module (1), preferably for quantum communication, quantum cryptography, and/or quantum key distribution (QKD), comprises a first and a second diffraction element, a wave-plate (4), and at least four single photon detectors (5), in order to enable a polarization analysis of single photons in two mutually unbiased bases and two orthogonal states per base. According to the invention, the first and second diffraction elements are polarization sensitive first and second dielectric metastructure gratings (2, 3), and the wave-plate (4) is arranged between the first and second dielectric metastructure grating (2, 3), and at least two detectors (5) are arranged in diffraction paths of the first diffraction element, and at least two detectors (5) are arranged in diffraction paths of the second diffraction element.enpatentEP4194822 A1EP20210212895