Preparation of metrological states in dipolar-interacting spin systems
Abstract
Spin systems are an attractive candidate for quantum-enhanced metrology. Here we develop a variational method to generate metrological states in small dipolar-interacting spin ensembles with limited qubit control. 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. The developed black-box optimization techniques for small spin numbers (N ≤ 10) are directly applicable to diamond-based nanoscale field sensing, where the sensor size limits N and conventional squeezing approaches fail.
Additional Information
We thank D. DeMille, D. Freedmann, A. Bleszynski Jayich, S. Kolkowitz, T. Li, Z. Li, R. Kaubruegger, Y. Huang, Q. Xuan, Z. Zhang, S. von Kugelgen, C-J. Yu, Y. Bao, P. Gokhale, N. Leitao, L. Martin and H. Zhou for helpful discussions. The investigation of sensing performance and state preparation under noise is based upon work supported by Q-NEXT (Grant No. DOE 1F-60579), one of the U.S. Department of Energy Office of Science National Quantum Information Science Research Centers. T.-X.Z. and P.C.M. acknowledge support by National Science Foundation (NSF) Grant No. OMA-1936118 and OIA-2040520, and NSF QuBBE QLCI (NSF OMA-2121044). S.Z. acknowledges funding provided by the Institute for Quantum Information and Matter, an NSF Physics Frontiers Center (NSF Grant PHY-1733907). Z.M. and F.T.C. acknowledge support by EPiQC, an NSF Expedition in Computing, under grants CCF-1730082/1730449; in part by STAQ under grant NSF Phy-1818914; in part by the US DOE Office of Advanced Scientific Computing Research, Accelerated Research for Quantum Computing Program.; and in part by NSF OMA-2016136. The authors are also grateful for the support of the University of Chicago Research Computing Center for assistance with the numerical simulations carried out in this work. Data availability. All relevant data supporting the main conclusions and figures of the document are available from the corresponding author on reasonable request. Code availability. All relevant code is available from the corresponding author upon reasonable request.Additional details
- Eprint ID
- 118781
- Resolver ID
- CaltechAUTHORS:20230111-282624100.10
- 1F-6057
- Department of Energy (DOE)
- OMA-1936118
- NSF
- ITE-2040520
- NSF
- OMA-2121044
- NSF
- PHY-1733907
- NSF
- CCF-1730082
- NSF
- CCF-1730449
- NSF
- PHY-1818914
- NSF
- OMA-2016136
- NSF
- Created
-
2023-02-09Created from EPrint's datestamp field
- Updated
-
2023-02-09Created from EPrint's last_modified field
- Caltech groups
- Institute for Quantum Information and Matter