Fiber quantum cryptography setup with auto-compensating scheme

摘要

This report is presented experimental setup for a quantum key distribution over a standard optical fiber.Information is encoded with the phase shift between two branches of the Mach-Zehnder interferometer. In order to make the system stable the auto compensated scheme of the Mach-Zehnder interferometer is used. All elements of the optical scheme are guided by the specialized processor. This method allows to make the key generation and accomplishing of all adjustments automatically. The problem of single photon measurement was investigated in the scope of the quantum cryptography application. For this purposes was constructed APD photodiodes single photon detectors.