Analytic tractability as a limiting constraint in quantum control of many-body spin systems

Talk

As quantum control of many-body spin systems approaches hardware-imposed performance limits, the assumptions that enable analytic tractability inevitably cease to function as organizing principles and instead become constraints.
Symmetry-based, closed-form design principles systematically exclude weak, device-specific mechanisms that dominate near-limit dynamics, thereby constraining achievable performance.
Here, we relax the tractability constraint through computational discovery that complements analytic reasoning, enabling many-body spin control beyond closed-form design.
In a solid-state spin ensemble, this approach uncovers control protocols that demonstrate clear advantages over analytically designed counterparts while resisting complete analytic description.
Crucially, these protocols are not arbitrary: they exhibit interpretable, repeatable structure that reveals organizing principles of near-limit many-body dynamics.
This structure enables reliable performance estimation across families of control solutions, improving the efficiency of computational exploration by approximately two orders of magnitude.
As a result, it becomes feasible to navigate hardware-resolved control design spaces far exceeding analytically tractable regimes, expanding the available control primitives from 8 symmetry-restricted operations to 26,400 quasi-continuous choices.
Fine-grained primitive variations are essential in the near-limit regime, enabling the precise capture of weak, hardware-specific effects in realistic devices.
Together, these results show that breaking the confinement imposed by analytic tractability requires integrating analytic reasoning with computational discovery in a unified framework, thereby enabling systematic advances in experimental capability and physical understanding.

Back to list