collaborators

6 papers

quant-ph2025

Bayesian frequency estimation at the fundamental quantum limit

James W. Gardner, Tuvia Gefen, Ethan Payne +6

Searching for a weak signal at an unknown frequency is a canonical task in experiments probing fundamental physics such as gravitational-wave observatories and ultra-light dark mat…

cond-mat.quant-gas2025

Multi-mode cooling of a Bose-Einstein condensate with linear quantum feedback

Zain Mehdi, Matthew L. Goh, Matthew J. Blacker +2

We theoretically investigate measurement-based feedback control over the motional degrees of freedom of an oblate quasi-2D atomic Bose-Einstein condensate (BEC) subject to continuo…

quant-ph2025

Multimode feedback cooling of the collective modes of a Bose-Einstein condensate

Ryan J. Thomas, Jordan A. McMahon, Zain Mehdi +5

We experimentally demonstrate cavity-free feedback cooling of the three lowest-lying collective modes of a Bose-Einstein condensate in a prolate harmonic trap. Using shadowgraph im…

quant-ph2025

Lindblad estimation with fast and precise quantum control

James W. Gardner, Simon A. Haine, Joseph J. Hope +2

Enhancing precision sensors for stochastic signals using quantum techniques is a promising emerging field of physics. Estimating a weak stochastic waveform is the core task of many…

quant-ph2024

Fast mixed-species quantum logic gates for trapped-ion quantum networks

Zain Mehdi, Varun D. Vaidya, Isabelle Savill-Brown +6

Quantum logic operations between physically distinct qubits is an essential aspect of large-scale quantum information processing. We propose an approach to high-speed mixed-species…

quant-ph2024

Simulating Feedback Cooling of Incoherent Quantum Mixtures

Kaiwen Zhu, Zain Mehdi, Joseph J. Hope +1

We develop a new approach for efficient and scalable simulations of measurement and control of quantum systems built upon existing phase-space methods, namely the Truncated Wigner…