PR42_Components for an Integrated Recirculating Frequency Shifter Device (NNX16AD14G-Y3)

We report and discuss measurements of silicon photonics components which comprise a recirculating variable-count frequency shifter (RVCFS) device. Summary of a Project Outcomes report of research funded by NASA.

Performance Analysis of a Multi-Function Mach-Zehnder Interferometer Based Photonic Architecture on SOI Acting as a Frequency Shifter

A photonic frequency shifter based on generalized Mach-Zehnder interferometer (GMZI) architecture is presented and experimentally validated. The circuit consists of four Mach-Zehnder modulators (MZM) in a 4 × 4 network bounded by two 4 × 4 multimode interference couplers and functionally equivalent to two parallel dual-parallel MZM (DP-MZM). The circuit can offer static bias free operation, virtual connectivity control of the components, and spatial separation of up- and down-converted carriers, which can be collected from separate ports without using any optical demultiplexing filters. Thus, the design permits remote heterodyning (advantages which cannot be obtained using a commercial DP-MZM or filter based optical frequency shifter). Experimental investigation shows deviation from ideal performance due to possible fabrication error and poor fiber-chip coupling. A carrier suppression of >20 dB and spurious sideband suppression >12 dB relative to the principal harmonics is achieved without any tuning for bias adjustment. In addition to the frequency conversion, the integration feasible circuit can also perform as a sub-carrier generator, IQ modulator, and frequency multiplier.

All-Fiber Frequency Shifter Based on an Acousto-Optic Tunable Filter Cascaded with a Tapered Fiber-Coupled Microcavity

An all-fiber acousto-optic frequency shifter (AOFS) based on an acousto-optic tunable filter (AOTF) cascaded with a packaged tapered fiber (TF)-coupled microsphere was proposed and demonstrated in both theory and experiment. The configuration has the advantages of easy alignment, robustness, compact size, and low cost, which will improve its further application, such as in the optical heterodyne detection technique (OHDT).

Акустооптические модуляторы с расширенной частотной полосой для волоконно-оптических линий

A modulator-frequency shifter with single-mode optical fibers for a radiation wavelength of 1064 nm has been developed and manufactured. The light beam was focused in the center of the sound column. Modulator switching time ≃ 18 ns. Operating mode: pulse, continuous. Total optical loss at center frequency: -3.2 dB. An expression for the frequency band of reception of the modulator is obtained. The estimates are in good agreement with the experimental data ≃ 40 MHz. It is shown that the use of a scheme with a focused beam makes it possible to implement a modulator with a minimum switching time ≃ (2-3) ns and a receiving frequency band ≃ (200-300) MHz.