PHYSICS PHD DISSERTATION DEFENSE: Saptarshi Chaudhuri
Ph.D. Candidate: Saptarshi Chaudhuri
Research Advisor: Kent David Irwin
Date: Monday, August 26, 2019
Time: 2pm
Location: Varian 355
Title: The Dark Matter Radio: A Quantum-Enhanced Search For QCD Axion Dark Matter
Abstract:
The nature of dark matter is one of the great mysteries in physics, providing compelling evidence for the existence of particles beyond the Standard Model. In this defense, I introduce the Dark Matter (DM) Radio, a tunable, lumped-LC oscillator search for axion and hidden-photon dark matter between 1 peV and 1 ueV. The design of DM Radio is motivated from fundamental optimization statements regarding impedance-matching to dark matter and electromagnetic searches subject to the Standard Quantum Limit on phase-insensitive amplification. I describe the DM Radio Pathfinder, the prototype detector using a 4K liquid-helium-cooled resonator that is searching for hidden-photon dark matter between 500 peV and 50 neV. First data from the Pathfinder are presented. I show that the sensitivity of DM Radio can be improved by using techniques evading the Standard Quantum Limit and propose the Radio-Frequency Quantum Upconverter, a device enabling the use of quantum metrology in DM Radio. The ultimate vision for DM Radio, a cubic-meter-volume resonant experiment operating at 10 mK with a 4 Tesla magnetic field and exploiting quantum metrology, is presented. This experiment will enable a probe of the QCD axion between approximately 4 neV and 1 ueV.