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The Owens Valley Radio Observatory Long Wavelength Array is a low radio frequency all-sky imaging radio interferometer. The full 352-element array will generate more than 2 TB of visibility data per hour of observation. One of the array’s primary science cases, the search for variable radio emission from exoplanets and for transients, require fast and high dynamic range interferometric imaging. Here we detail the design and implementation of a two-pipeline infrastructure that minimizes development cost: an offline pipeline that facilitates experimentation with existing pack-ages, and a real-time pipeline that minimizes overhead. 

Thin-film lithium niobate has emerged as an excellent, multifaceted platform for integrated photonics and opto-electronics, in both classical and quantum domains. We introduce a novel, to the best of our knowledge, dual-capacitor electrode layout for an efficient interface between electrical and optical signals on this platform. It significantly enhances the electro-optical modulation efficiency to an exceptional voltage–length product of $0.64\mathrm{V}\cdot <\#comment/>\mathrm{c}\mathrm{m}$, thereby lowering the required electric power by many times. This technique can boost the performance of growing applications at the interface of integrated electronics and optics, such as microwave photonics, frequency comb generation, and telecommunication transmission. 

Wavelength transduction of single-photon signals is indispensable to networked quantum applications, particularly those incorporating quantum memories. Lithium niobate nanophotonic devices have demonstrated favorable linear, nonlinear, and electro-optical properties to deliver this crucial function while offering superior efficiency, integrability, and scalability. Yet, their quantum noise level—a crucial metric for any single-photon-based application—has yet to be investigated. In this work, we report the first, to the best of our knowledge, study with the focus on telecom to near-visible conversion driven by a small detuned telecom pump for practical considerations in distributed quantum processing over fiber networks. Our results find the noise level to be on the order of ${10}^{-<\#comment/>4}$photons per time-frequency mode for high conversion, allowing faithful pulsed operations. Through carefully analyzing the origins of such noise and each’s dependence on the pump power and wavelength detuning, we have also identified a formula for noise suppression to ${10}^{-<\#comment/>5}$photons per mode. Our results assert a viable, low-cost, and modular approach to networked quantum processing and beyond using lithium niobate nanophotonics. 

Abstract We report the detection and interferometric localization of the repeating fast radio burst (FRB) source FRB 20220912A during commissioning observations with the Deep Synoptic Array (DSA-110). Two bursts were detected from FRB 20220912A, one each on 2022 October 18 and 2022 October 25. The best-fit position is (R.A. J2000, decl. J2000) = (23:09:04.9, +48:42:25.4), with a 90% confidence error ellipse with radii ±2″ and ±1″ in R.A. and decl., respectively. The two bursts are polarized, and we find a Faraday rotation measure that is consistent with the low value of +0.6 rad m⁻²reported by CHIME/FRB. The DSA-110 localization overlaps with the galaxy PSO J347.2702+48.7066 at a redshiftz= 0.0771, which we identify as the likely host. PSO J347.2702+48.7066 has a stellar mass of approximately 10¹⁰M_⊙, modest internal dust extinction, and a star formation rate likely in excess of 0.1M_⊙yr⁻¹. The host-galaxy contribution to the dispersion measure is likely ≲50 pc cm⁻³. The FRB 20220912A source is therefore likely viewed along a tenuous plasma column through the host galaxy.