Tian Xing Zheng: Preparation of Metrological States in Dipolar-Interacting Spin Systems

Seminar

Location: Elings Hall rm. 1601

Speaker

Tian-Xing Zheng

University of Chicago

Abstract

Spin systems are an attractive candidate for quantum-enhanced metrology. In this presentation, I will introduce a variational method to generate metrological states in small dipolar-interacting spin ensembles with limited qubit control, as present in nanoscale quantum sensing applications. The simulation results show that for both regular and disordered spatial spin configurations the generated states enable sensing beyond the standard quantum limit (SQL) and, for small spin numbers, approach the Heisenberg limit (HL). Depending on the circuit depth and the level of readout noise, the resulting states resemble Greenberger-Horne-Zeilinger (GHZ) states or Spin Squeezed States (SSS). Sensing beyond the SQL holds in the presence of finite spin polarization and a non-Markovian noise environment. Potential experimental platforms include dipolar-interacting ensembles of NV centers, nitrogen defects in diamond (P1), rare-earth-doped crystals, and ultra-cold molecules. I will also discuss our recent experimental progress on the cryogenic confocal microscope platform.

Bio

I’m currently a graduate student working with Prof.Peter Maurer at the University of Chicago. My research focus on developing entanglement enhanced quantum sensor in NV systems and new types of quantum sensors for nanoscale NMR applications. I’m also working on building up a dilution fridge platform with optical/microwave accesses for the experimental studies of the quantum sensors. Before joining Maurer Lab, I did my undergraduate thesis about the Zeeman slower for Strontium ultracold atom with Prof.Xibo Zhang at Peking University.