Experimental Study of Quantum Random Number Generation Using Polarization Switching in Gain-Switched VCSELs.

We have experimentally demonstrated that the random excitation of the linear orthogonal polarization modes of a gain-switched vertical-cavity surface-emitting laser (VCSEL) can be used for quantum random number generation. Our VCSEL presents polarization switching under continuous wave operation. Adjusting the modulation conditions and sampling times, both polarization modes of the VCSEL can be excited with equal probability. Random bits are obtained comparing the two orthogonal polarized signals at a sampling time. The random bits obtained pass some of the National Institute of Standards and Technology (NIST) statistical tests.