Optical computing by injection-locked lasers

TL;DR

This paper demonstrates a programmable optical logic gate using injection-locked VCSELs, enabling ultrafast, wavelength-independent, all-optical logic operations with potential for optical computing.

Contribution

It introduces a novel nonlinear optical scheme based on normalization operations for programmable logic gates with high-speed switching.

Findings

Switches between AND and OR at 1 GHz

Achieves BER of 10e-6

Operates without changing wavelength or encoding

Abstract

A programmable optical computer has remained an elusive concept. To construct a practical computing primitive equivalent to an electronic Boolean logic, one should find a nonlinear phenomenon that overcomes weaknesses present in many optical processing schemes. Ideally, the nonlinearity should provide a functionally complete set of logic operations, enable ultrafast all-optical programmability, and allow cascaded operations without a change in the operating wavelength or in the signal encoding format. Here we demonstrate a programmable logic gate using an injection-locked Vertical-Cavity Surface-Emitting Laser (VCSEL). The gate program is switched between the AND and the OR operations at the rate of 1 GHz with Bit Error Ratio (BER) of 10e-6 without changes in the wavelength or in the signal encoding format. The scheme is based on nonlinearity of normalization operations, which can be used to construct any continuous complex function or operation, Boolean or otherwise.