(Phys.org) A research team based at the Johns Hopkins University Applied Physics Laboratory (APL) applied two theoretical tools of quantum information to types of extremely sensitive signal detection tasks. Their research suggests that honing this sensitivity to detect signals while rejecting background noise will enable the use of quantum detectors even when this surrounding noise is strong relative to the signal of interest.
“This field has seen a lot of recent interest through theoretical progress and impressive experimental results on a variety of platforms,” said Paraj Titum, a quantum scientist in APL’s Research and Exploratory Development Department and the lead author of the paper. “Our results are readily implementable in a variety of quantum computing and quantum sensing platforms such as superconducting qubits, NV-diamonds, and Silicon Carbide.”
The authors applied filter functions and optimal quantum control theories to a use case of quantum bit (qubit) sensors that mirror a classic problem in signal detection theory: optimal detection of a known signal from background noise with a controllable quantum sensor. The research team obtained analytical insight into the optimal control protocol when the background noise is white.