Researchers create novel photonic chip

Phys.org  February 2, 2021 Photonic Digital‐to‐analog converters (DAC) enable a seamless signal conversion with respect to both energy efficiency and short signal delay. Using a silicon photonic chip platform, a team of researchers (Washington University, UCLA) has developed a coherent parallel photonic DAC concept along with a 4‐bit prototype capable of performing as DAC without optic–electric–optic domain crossing. This guarantees a linear intensity weighting among bits when operating at high sampling rates (50 GHz), featuring an exceptional sampling efficiency (> 100 GS −1 ) and small footprint (≈1 mm2) in an 8‐bit implementation. The photonic DAC enables seamless interfaces of next‐generation data processing hardware […]

Photonics researchers report breakthrough in miniaturizing light-based chips

Nanowerk  August 27, 2020 Researchers at the University of Rochester made an important step towards miniaturizing functional components on thin-film lithium niobate (LN) platform by developing high-speed LN electro-optic modulators, based upon photonic crystal nanobeam resonators. The devices exhibit a significant tuning efficiency, broad modulation bandwidth of 17.5 GHz, all with a tiny electro-optic modal volume. The modulators enable efficient electro-optic driving of high-Q photonic cavity modes in both adiabatic and non-adiabatic regimes and allow electro-optic switching at 11 Gb s−1 with a bit-switching energy as low as 22 fJ. The demonstration provides a crucial foundation for realizing large-scale LN […]

Photonic microwave generation using on-chip optical frequency combs

Science Daily  April 20, 2020 Soliton microcombs can now be built using CMOS-compatible photonic integrated circuits. However, they operate with repetition rates significantly beyond those that conventional electronics can detect, preventing their use in microwave photonics. Researchers in Switzerland have demonstrated soliton microcombs operating in two widely employed microwave bands, the X-band (~10 GHz, for radar) and the K-band (~20 GHz, for 5G). Driven by a low noise fibre laser, these devices produce more than 300 frequency lines within the 3 dB bandwidth, and generate microwave signals with phase noise levels comparable to modern electronic microwave oscillators. The results establish integrated microcombs as […]

Programming light on a chip

Eurekalert  January 8, 2019 An international team of researchers (USA – Harvard University, Howard University, China) has demonstrated a ‘photonic molecule’ with two distinct energy levels using coupled lithium niobate microring resonators and control it by external microwave excitation. They showed that the frequency and phase of light can be precisely controlled by programmed microwave signals and on-demand optical storage and retrieval by reconfiguring the photonic molecule into a bright–dark mode pair. These results open doors to applications in microwave signal processing, quantum photonic gates in the frequency domain and exploring concepts in optical computing and topological physics…read more. TECHNICAL […]