Generació de números aleatoris quàntics basats en la dinàmica de polarització en VCSELs
Mir Pou, Blanca
Abstract
Random numbers are essential in a great variety of applications ranging from stochastic simulations to secure communications. In this thesis, we report a technique for quantum random number generation based on the dynamics of light polarization in a vertical-cavity surface-emitting laser (VCSEL). We show that two linearly polarized modes with slightly different wavelengths and gains appear within the cavity of the VCSEL laser. Due to spontaneous emission noise, VCSELs undergo random polarization switching at certain bias currents. We experimentally analyze the probability of appearance of each mode as a function of the biasing conditions. By periodically modulating a VCSEL at the polarization switching region defined under continuous-wave operation, random digits can be generated directly from the output of the pulsed VCSEL at a much higher bit rate. The results presented in this research demonstrate the feasibility of generating random numbers at rates up to 100 Mbit/s using a commercial VCSEL.