Speaker
Description
Power-over-Fiber (PoF) provides galvanically isolated power delivery to electronics operating in cryogenic, high-voltage, and electromagnetically sensitive environments. A principal challenge for scaling PoF beyond individual channels is the cold-stage heat load associated with optical-to-electrical conversion. We are developing a pulsed PoF architecture in which optical power is duty-cycled and combined with cryogenic energy storage and local regulation, decoupling peak electronic load from instantaneous optical power.
We will present results from the SLAC PoF R&D program, including cryogenic characterization of optical power converters in collaboration with Michigan State University, development of a programmable pulsed laser driver, cryogenic-compatible energy-storage and low-dropout-regulator electronics, and hardware for cryogenic characterization of FBK digital silicon photomultipliers. Measurements in liquid nitrogen have demonstrated optical-to-electrical conversion efficiencies approaching 60% (808nm,77K), providing a baseline for evaluating the thermal benefit of pulsed operation.
The next phase will integrate these components into a reusable cryogenic power platform and characterize efficiency, output noise, transient response, and thermal load under dynamic detector-electronics loads down to 77 K. The platform will also provide isolated power for cryogenic characterization of 28-nm ASICs developed through the complementary Cryo-PDK effort.
We are additionally extending the concept of galvanic isolation to 4 K quantum instrumentation by investigating optical bias of SQUID series arrays. A cryogenic photodiode operated in photovoltaic mode will be characterized for loaded I–V response, responsivity, temperature dependence, and conversion of laser-intensity noise into bias-current noise, followed by a direct comparison of optically and electrically biased SQUID operation. These studies explore PoF not as an experiment-specific power system, but as a general low-noise, low-thermal-load power architecture for cryogenic detector and quantum instrumentation.