We identify a strong quantum Mpemba effect in which a many-body ground state heats faster than every Gibbs state at finite positive temperature under the same dissipative dynamics within a fixed-color sector. In ferromagnetic
SU(N) exchange systems with local dephasing, exact coherence shells confine the ground-state evolution and exclude all slower Liouvillian modes. Its relaxation rate is fixed by the bath, independently of system size, exchange graph, and integrability. We derive an energy-resolved sign criterion that guarantees a slower thermal contribution throughout the positive-temperature range. An exact finite-chain solution proves this rate inversion, and symmetry-resolved calculations confirm the criterion in larger spin-one chains, including nonintegrable exchange. The zero-temperature endpoint of a continuous Gibbs family can therefore be dynamically isolated by its exact exclusion from slow relaxation channels.
The accuracy of quantum state estimation and dynamic signal tracking is crucial for the reliability and performance of quantum sensing instruments such as spin-exchange relaxation-free (SERF) co-magnetometers and gyroscopes. To improve the performance of the SERF gyroscope for future quantum navigation applications, an adaptive quantum estimation and closed-loop optimal control method based on fault detection and isolation (FDI) and an adaptive Kalman filter is proposed. Firstly, the system model of the SERF gyroscope is established, and a real-time angular velocity measurement method is provided. Then, the stochastic model of the SERF gyroscope is analyzed based on an adaptive quantum Kalman observer to track and compensate for real-time angular velocity error with the assistance of FDI. Finally, the real-time LQI (Linear-Quadratic-Integral) control method is adopted to improve the dynamic response and accuracy of the overall system. Simulations and experiments are conducted based on the SERF gyroscope platform. The results show that the system can achieve optimal tracking accuracy for polarization estimation and effectively isolate fault information. The dynamic response time has been improved by 58.2% under environmental disturbance, which provides a foundation for subsequent navigation applications.
Intrinsic heating is generally regarded as a secondary consequence of optical excitation in rare-earth (RE
3+)-doped materials. Here, we demonstrate that intrinsic thermo-optical feedback can drive the transient dynamics of optically excited RE
3+ systems. To isolate this mechanism, we develop a minimal coupled population-temperature model that describes the interplay among optical excitation, temperature-dependent non-radiative relaxation, heat generation, and thermal dissipation. The model predicts the emergence of a threshold excitation power associated with intrinsic thermo-optical feedback, giving rise to pronounced slowing down of the transient dynamics, non-monotonic evolution of the characteristic transient time, population overshoot, and accelerated relaxation above threshold. These phenomena originate from the progressive establishment of a positive feedback loop linking temperature, non-radiative relaxation, quantum efficiency, and heat generation. Our results demonstrate that temperature should no longer be regarded merely as a passive external parameter, but rather as an active dynamical variable capable of continuously reshaping the relaxation pathways of the system. More broadly, this work establishes intrinsic thermo-optical feedback as a general framework for understanding nonlinear transient phenomena in optically excited RE
3+ materials and provides a complementary perspective for interpreting threshold-like optical responses beyond conventional photon-avalanche mechanisms.