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arXiv · 2607.25005

Invariant-based master equation applied to driven qutrit coupled to a bath and a leaky cavity

Sagarika Basak·A. Javadi·D. Blume
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Abstract

We employ a generalized approach to the master equation for driven open $N$-level ($N>2$) quantum systems using Lewis-Riesenfeld invariants, which avoids the driving-strength restrictions inherent to conventional approaches. We show that the invariant-based master equation provides a unifying generalized framework, which reduces to the frequently employed laboratory-frame master equations and the less frequently employed rotating-frame master equation framework under appropriate simplifications. Extending the prototypical two-level system, we show that the inclusion of another state coupled to the ground state via reservoir-induced dephasing gives rise to qualitatively new dissipative behaviors that are, in general, not captured by standard approximations. We also apply the invariant-based master equation framework to a driven quantum dot coupled to a leaky cavity, demonstrating the framework's ability to capture relevant dissipative dynamics without additional assumptions. Our work paves the way for quantum-control applications in the presence of dissipation.

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Sagarika Basak, A. Javadi, D. Blume. 2026-07-27. Invariant-based master equation applied to driven qutrit coupled to a bath and a leaky cavity. https://doi.org/10.1103/lp44-ll2f

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