Carrie Weidner

Research interests and activities

I am interested broadly in the control and manipulation of quantum systems. I am originally trained as an experimental cold atom physicist, but since my PhD studies in JILA at the University of Colorado Boulder, my research has branched out substantially. While we still focus on atom-based systems, my main research foci are:

• Quantum-enhanced inertial sensing with ultracold atoms trapped in phase-modulated (or shaken) optical lattices. We hope to build a system capable of performing six-axis inertial sensing in a robust and tunable system. This work is supported by EPSRC, InnovateUK, and our industry partners Infleqtion, Inc.

• Atoms and integrated photonics. A recent proposal in our group has discussed how we can develop chip-scale devices for trapping ultracold atomic gases in the evanescent field above integrated photonic waveguides. We hope to build these devices and demonstrate scalable, CMOS-compatible, and mass-manufacturable atom-photonic systems.

• My group also has a nascent project where we are looking at the feasibility of scalable opto-atomic neural networks. These systems are potentially useful for developing sustainable alternatives to in silico neuromorphic computing methods, which could possibly alleviate the energy demands of the data centres that drive, e.g., large-language models.

• The generation of interesting quantum states in optical lattices via optimal control. We have recently shown that GKP states can be deterministically generated by controlling the wavefunction of atoms trapped in the individual sites of a very deep optical lattice.

In the above figure, (a) and (c) show ideal Wigner functions for the GKP states with 10 dB squeezing, and (b) and (d) show the optimized Wigner functions that can be obtained in an experimental system [note the data is simulation only, we are building the experiment now!].

• Robust quantum control. In collaboration with Profs. Edmond Jonckheere (emeritus, USC), Frank Langbein (Cardiff), and Sophie Schirmer (Swansea), I am working on the design, implementation, and analysis of robust quantum control protocols in practical quantum systems.
• Quantum physics education. I am broadly interested in graduate-level experimental physics training [in collaboration with Prof. Heather Lewandowski, JILA], as well as equity of access in quantum physics education through simulation tools and 3D-printable components for use in quantum demonstration tools and experiments.

I am also collaborating with others in QET Labs on atoms and integrated photonics [with Prof. Martin Cryan], quantum memories in hot and cold atom vapours [with Dr Alex Clark], and atomic systems for indefinite causality [with Dr Giulia Rubino].

• Magnetic field imaging based on single-pixel imaging of the Faraday effect in hot atom vapour. Eventually we plan to use squeezed light generated by polarization self-rotation in the vapour to enhance the sensitivity of our magnetometers. This project is supported by the QuantIC imaging and sensing hub.