Figure 1
From: Effect of external magnetic fields on practical quantum random number generator
The architecture of the QRNG is based on quantum phase fluctuation. A laser emits a continuous beam that enters the Michelson interferometer through the circulator. One output port of the interferometer is monitored by a PM. A PID program analyzes the measured results of the PM and sends a signal to the PC. The PC could adjust the PS in real-time. The other output port of the interferometer is measured by a PD. And the measured voltage signal of the PD is digitized by an ADC. BS: beam splitter, PS: phase shifter, PM: power meter, PC: piezo controller, FRM: Faraday rotator mirror, PID: proportional-integral-derivative control, PD: photodetector, ADC: analog-to-digital converter