title: Stochastic logic gate that exploits noise and polarization bistability in an optically injected VCSEL.
abstract: We study numerically the dynamics of a vertical-cavity surface-emitting laser (VCSEL) with optical injection and show that the interplay of polarization bistability and noise yields a reliable logic output to two logic inputs. Specifically, by encoding the logic inputs in the strength of the light injected into the suppressed polarization mode of the VCSEL (the so-called 'orthogonal' injection), and by decoding the output logic response from the polarization state of the emitted light, we demonstrate an all-optical stochastic logic gate that exploits the ubiquitous presence of noise. It gives the correct logic output response for as short as 5 ns bit times when the dimensionless spontaneous emission coefficient, β(sp), is within the range 10(-4)-10(-1). Considering that typical values of β(sp) in semiconductor lasers are in the range 10(-5)-10(-4), the VCSEL-based logic gate can be implemented with nowadays commercially available VCSELs, exploiting either their intrinsic noise, or external and background noise sources.
authors.affiliation: Departament de Fisica i Enginyeria Nuclear, Universitat Politecnica de Catalunya, Colom 11, 08222 Terrassa, Spain. sandro.perrone@gmail.com
authors.forename: Sandro
authors.initials: S
authors.lastname: Perrone
authors.forename: Ramon
authors.initials: R
authors.lastname: Vilaseca
authors.forename: Cristina
authors.initials: C
authors.lastname: Masoller
mesh_terms: D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D054023:Lasers, Semiconductor; D008027:Light; D015233:Models, Statistical; D012542:Scattering, Radiation; D059629:Signal-To-Noise Ratio