Measurement and active compensation of polarization drifts in a fiber quantum channel used for teleportation

Measurement of the polarisation state of the photons of a laser beam is described in the paper. The measuring optical device consists of symmetric beamsplitters (BS), a polarizing beamsplitter (PBS), polarizers, a quaterwaveplate and light detectors. With the stabilized quantum channel, it is possible to perform high fidelity quantum teleportation experiments.