Date of Award

Spring 5-27-2026

Document Type

Thesis (Undergraduate)

Department

Physics and Astronomy

First Advisor

Alexander Rimberg

Abstract

From improving qubit readout to real world medical technology, fast and ultrasensitive electrometry has many real world applications. The primary goal of the overarching project is to improve ultrasensitive charge detection using methods involving cavity-embedded Cooper pair transistor (cCPT) devices. This project hopes to accomplish this by using the gate-tunability of the cCPT to reduce the 1/f-noise, a type of low-frequency noise that can interfere with the cCPT’s measurement operability. By using a Pound-Drever-Hall (PDH) feedback loop-inspired scheme that can adjust the cCPT gate, this project hopes to improve the stability of the cCPT’s resonant frequency against the 1/f-noise, in turn making the ultrasensitive charge detection more efficient, accurate, and sensitive.

In this project, I worked on the measurement circuit of the cCPT’s PDH feedback loop. After conducting extensive literature review to understand the context of this lab, I propose the replacement of the successive detection logarithmic video amplifier (SDLVA) with a microwave envelope detector in order to improve the extraction of the error signal from the PDH feedback loop. Doing so would help improve the stability of the cavity’s resonant frequency, improving the cCPT as a fast, ultrasensitive electrometer. I will compare theoretically expected results derived from analysis of the specifications of each device to experimental results and use these results to compare the SDLVA and envelope detector as methods of extracting error signals.

Download

Included in

Physics Commons

Share

COinS