QUANTUM CRYPTOGRAPHY DEVICE AND SIGNAL LIGHT POLARIZATION COMPENSATING METHOD

摘要

A quantum cryptography device for performing a quantum-encrypted communication between a transmitter (10) having a transmission-side interferometer (13) and a receiver (20) having a reception-side interferometer (22) is configured to perform a temperature adjustment such that the temperature of the reception-side interferometer (22) is a polarization-independent temperature that causes the waveguide length difference of the reception-side interferometer (22) to be equal to an integral multiple of the beat length, and the quantum cryptography device is further configured to apply a pressure to the waveguide of the reception-side interferometer (22), thereby adjusting the polarization-independent temperature.