Cooperative control and geometric amplification in dissipative quantum systems
- URL: http://arxiv.org/abs/2606.30073v1
- Date: Mon, 29 Jun 2026 10:05:45 GMT
- Title: Cooperative control and geometric amplification in dissipative quantum systems
- Abstract summary: We show that dissipation itself becomes a control resource when fast relaxation channels are deliberately exploited.<n>We demonstrate this mechanism for a qubit subject to non-unital and anisotropic Bloch relaxation.
- Score: 0.0
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: In the control of dissipative quantum systems, the slow relaxation modes usually set the ultimate manipulation timescale. Here we show that this apparent bottleneck can be bypassed: dissipation itself becomes a control resource when fast relaxation channels are deliberately exploited. We demonstrate this mechanism for a qubit subject to non-unital and anisotropic Bloch relaxation. A short coherent pulse first reorients the Bloch vector onto a fast dissipative eigendirection; the subsequent free relaxation then carries the state close to the target, with at most one final corrective pulse. The resulting bang-drift-bang strategy is cooperative: coherent control selects the dissipative channel, while the bath performs most of the transfer. For axial targets, we obtain a closed-form speedup over passive relaxation by a factor of order $κ=T_1/T_2\gg1$. For out-of-equilibrium non-axial targets, an additional off-axis interception mechanism provides a further geometric amplification, allowing the hitting-time speedup, still normalized to the axial passive-reset time, to exceed the axial $κξ$ benchmark by an extra factor of four to five. The mechanism therefore directly connects to standard Bloch-vector qubit platforms, including magnetic-resonance spins, nitrogen-vacancy centers, and superconducting circuits, with potential relevance for quantum-control and fast-reset protocols.
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