Benchmarking exchange-only control of a 48-spin singlet manifold
HRL Quantum Team, Microsoft Collaborators, :, Stephen Carr, Matt Abbitt, Michael Abraham, Edwin Acuna, I. Alverado, Carter Andrews, Hussein Anton, Katherine M. Beech, Aaron J. Bluestone, Jacob Z. Blumoff, Matthew G. Borselli, Brydon Boyd, Jacob T. Boyer, Peter Brewer, Steven L. Brown, Joseph D. Broz, Tyler A. Cain, John B. Carpenter, Faustin W. Carter, Brittany Carter, Matthew D. Chambers, James M. Chappell, Kevin C. Chen, Edward H. Chen, Maxwell D. Choi, Matthew N. H. Chow, Justin E. Christensen, Aaron M. Chronister, Andrew M. Clapper, Michael D. Cornelius, Gregory M. Crosswhite, Stanislav Culaclii, Erik S. Daniel, Dominic Daprano, John K. David, Charles R. Elliott, Kevin Eng, Colin P. Feeney, David J. Fialkow, Dylan H. Finestone, Bryan H. Fong, Richie Fu, Zachary A. Geiger, Bradley W. Greene, Rafael Guerra-Fuentes, Hrayr K. Gurgenian, Alex Hamill, Brooke M. Hardesty, Jim W. Harrington, Alex Hirman, Donald A. Hitko, Silas Hoffman, Dominic Holloman, Daniel R. Hulbert, Jake Hundley, Clayton A. C. Jackson, Paul C. Jerger, B. Johnson, Aaron M. Jones, Michael P. Jura, Adour V. Kabakian, Tyler Keating, Joseph Kerckhoff, Andrey A. Kiselev, Patrick W. Krantz, Thaddeus D. Ladd, Sanaaya Lakdawala, Elias Lawson-Fox, Alwina R. Liu, Dwight Luhman, Manny Macias, Theodore K. Macioce, Ryan M. Martin, Daniel S. Matic, Gavin C. Mazur, Ryan McGeehan, Olivia Means, Austin Meyer, Samuel Mumford, Tina Niknejad, Riley P. O'Neil, Andrew Pan, Winston Pouse, Eric M. Prophet, Matthew D. Reed, Marcus Rentie, Alec Roberson, Zechariah Rogers, Golam Sabbir, Spencer Sager, Christopher D. Sanborn, Jonathan Sanchez, Rachel H. Sarmiento, Christian J. Schnaible, Cole Scott, Aaron Smith, Daniel E. Smith, James Soash, Kevin C. Staley, Andrea Su, Bo Sun, Christopher M. Swank, Noah Swimmer, Charles Tahan, Bryan J. Thomas, Yessica Torres, Alan Tran, Ivan Tran, James R. van Meter, Franklin Vartanian, John Samuel Venker, Daniel Volya, Annette L. Wagner, Daniel R. Ward, Aaron J. Weinstein, Abigail L. Wessels, Thomas V. Westrick, Evan T. White, Randall M. White, Parker Williams, Catrina E. Wilson, Courtney P. Wilt, Matthew Wingert, Clifford S. YoungSciortino, Andrew Ziegler
arXiv 2610.07393首次发表：更新：
发表机构
HRL Quantum Team; Microsoft Collaborators（HRL量子团队; 微软合作者）
Exchange-only quantum computing benefits from high fidelity and straightforward control afforded by the exchange interaction. However, independently controllable qubits must be encoded into subsystems of at least three electron spins, restricting computation to only a fraction of the available spin Hilbert space. The remaining states are treated as leakage and used only transiently in gate sequences. By contrast, a quantitative, system-wide measure of exchange-only performance can exploit the full available Hilbert space, including states conventionally treated as leakage. Here, we apply this approach to arrays of up to 48 electron spins, accessing a total-spin-zero Hilbert space with dimension exceeding $2^{40}$. Measurements of out-of-time-order correlators (OTOCs) reveal rich scrambling dynamics and demonstrate access to regimes relevant to quantum computational advantage. Using generalized forms of cross-entropy and mirror randomized benchmarking, we also assess the aggregate performance of the full exchange-only system per fundamental two-body interaction: the two-spin exchange. We obtain an effective system-level error of $3 \times 10^{-4}$ per exchange, incorporating the complete experimental control sequence and all associated noise sources. This value is up to an order of magnitude lower than those reported from comparable benchmarks on other platforms at the time of writing.
