Dissertation Research
Princeton University
Anticipated Defense: December 2026
My thesis work has been in operationalizing sub-GHz Kinetic Inductance Traveling Wave Parametric Amplifiers (KI-TWPAs) for the Princeton Axion Search (PXS). PXS is laboratory-scale search for a dark matter particle candidate, the axion, at mass ranges the correspond to the transitional region between lumped-element and cavity haloscope search techniques.
This search range poses unique challenges in developing quantum-limited readout schemes. Existing high-electron-mobility transistor (HEMT) amplifiers do not have sufficent noise characteristics in this frequency range, however KI-TWPAs are an emergent technology that has the capacity to meet the quantum-limited needs. Recent improvements in the KI-TWPA designs make it feasible to integrate these amplifiers in Dilution Refrigerator environments. We work in close collaboration with fabrication to improve the design stack. Our efforts with these amplifiers have demonstrated new state of the art performance for gain and noise measurement in the sub-GHz regime. Some of the work we provide in this effort is custom cabling that achieves greater gain and bandwidth through improved impedance matching, designing lumped-elemet microwave filters made from superconducting traces, and noise-temperature measurement techniques that provide the necessary precision to make measurements approaching the standard quantum limit.
Laboratory Work
A collection of research efforts outside of publication have been:
- Developing commercial grade Cryogenic Coax - Developed laboratory methods to fabricate stainless steel, copper, and superconducting Niobium-Titanium coaxial cable that outperformed commercially available product.
- Analog Control Circuits for Cryogenic Microwave Switches - Designed and fabricated an analog control circuit and command line interface to operate microwave multi-pole switches at sub-kelvin temperatures.
- Designing High-Current leads for Cryogenic Magnets - Designed and tested current leads that carried 300 Amps to 4K in a conduction-cooled cryostat
- Laboratory Software Development - Hosted GitLab, integrated Grafana and InfluxDB for timeseries data, wrote variety of python and shell control scripts to automate experiments.
PXS Publications
Our recent group publications include:
- Passive pyrolytic graphite heat switch for sub-Kelvin coolers - We achieved a mechanism to replace expensive gas-gap heat switches with inexpensive grapihte sheet for thermal connections that do not require an active switch