Low-noise delays from dynamic Brillouin gratings based on perfect Golomb coding of pump waves

Abstract

A method for long variable all-optical delay is proposed and simulated, based on reflections from localized and stationary dynamic Brillouin gratings (DBGs). Inspired by radar methods, the DBGs are inscribed by two pumps that are comodulated by perfect Golomb codes, which reduce the off-peak reflectivity. Compared with random bit sequence coding, Golomb codes improve the optical signal-to-noise ratio (OSNR) of delayed waveforms by an order of magnitude. Simulations suggest a delay of 5 Gb/s data by 9 ns, or 45 bit durations, with an OSNR of 13 dB.