Quantum Science and Technology

Quantum Mpemba effect: anomalous relaxation of multi-spin system under local noise

晓旭宁, Zhen-Dong Wei, Wei‐Bin Yan, Zhong‐Xiao Man, Yun‐Jie Xia, Ying-Jie Zhang, Qing-yu Cai

Published Oct 7, 2026• 0 citations

Abstract

Abstract The quantum Mpemba effect (QMPE) is characterized by a state initially farther from equilibrium relaxing faster than one closer to it. In this work, we investigate the QMPE in an open central-spin model, and examine whether the QMPE emerges when the spins’ system is subjected to their independent noisy environment for different initial states. Simultaneously, we analyze the influence of the noisy environment on the dynamics and demonstrate that tuning local noise strengths can induce the QMPE. Furthermore, we systematically explore finite-size effects by varying the number of peripheral spins. In addition, we investigate the Pontus Mpemba effect within the same framework, demonstrating that an auxiliary decohering environment can accelerate the approach to stationarity. To observe the effect, we select the trace distance, energy, and l 1 -norm coherence as observables. By combining initial-state engineering (global rotation operations) with the modulation of the noisy environment, we clearly reveal the physical mechanisms for inducing and controlling the QMPE in this model. Our results show that both rotating the initial states and applying non-uniform local noises can alter the relaxation rate ordering among different states, leading to crossings in the evolution curves of various physical quantities, that is, the realization of the QMPE. This finding provides a new perspective for manipulating anomalous relaxation behavior in the quantum many-body system and open quantum system.

DOI: 10.1088/2058-9565/aeb157

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