Hanson Nguyen

Hanson Nguyen

Biography

Hanson H. Nguyen is a rising senior at the Barrett Honors College atASU, majoringin Electrical Engineering and minoring in Mathematics. His research has centered on next-generation integrated-circuit platforms—ranging from photonic to superconducting devices—that promise secure, energy-efficient building blocks for new computing regimes, including quantum and high performance computing. He has joined research groups atASU, MIT, and Purdue, published two first-author papers, and presented both at local and international conferences. Hanson plans to pursue a PhD in Applied Physics to continue developing devices that address today’s computational demands with an emphasis on security and sustainability.Committed to accessibility in STEM education, Hanson has mentored K-12 teachers andstudents, and designed hands-on tools and curricula through an NSF-funded ResearchExperiences for Teachers program. He is currently a student ambassador for ASU’s Electrical Engineering department. In his free time, Hanson enjoys spinning records, doodling over lecture notes, and reading comics.

Abstract

Thermal and electronic reset times of superconducting nanowire single photon detectors

Superconducting nanowire single-photon detectors (SNSPDs) are ultra-sensitive devices capable of detecting individual photons with high detection efficiency, ultra-low dark count rates, and record low timing jitter time. Thus, SNSPDs have been valuable for applications that require precise photon detection or counting, such as quantum optics, fiber-optic communications, and LiDAR systems. These detectors operate by biasing a superconducting nanowire just below its maximum superconducting current, where the absorption of a single photon can disrupt the superconductivity, leading to the formation of a resistive region. After each detection event, the device undergoes a recovery process governed by the electronic reset time, which determines how quickly the bias current returns, and the thermal relaxation time, which dictates how rapidly the nanowire cools. Here, we model these processes using electrothermal SPICE simulations and design a cryogenic measurement scheme to determine the reset time of SNSPD devices. By illuminating the detector with a continuous-wave laser and recording photon arrival times, we apply statistical analyses to the photon interarrival times. We observe the kinetic-inductance-limited reset time, as well as thermal dynamics manifesting through after-pulsing, relaxation oscillations, and latching, which provides insight into how electronic and thermal reset dynamics jointly determine the maximum count rate of SNSPDs.