Exactly solvable model of suppression of quantum decoherence

Adriana Marais, Ilya Sinayskiy, Francesco Petruccione +1 more

Nima Arkani-hamed A, John E. Sipe

Sachiko Kitajima, Masashi Ban, Toshihico Arimitsu +1 more

By controlling externally applied pulses, we find suppression of decoherence on the basis of an exactly solvable quantum mechanical model. This is intuitively recognized in terms of an effective potential function produced by pulse application. Time evolution of spin variables is explicitly determined.

Mustafa Boudjerada

This note studies the role of a quantum mediator in gravitationally induced entanglement and decoherence using an exactly solvable dynamical mediator model. Two masses in spatial superposition interact through a mediator mode described by a displaced-oscillator Hamiltonian. The model provides a unified description of two regimes: when the mediator returns to its original state, it leaves behind pure entanglement between the masses through virtual excitation; when the mediator carries which-path information, it becomes a physical record that reduces coherence and suppresses entanglement. The work proves an exact record–decoherence relation: the loss of coherence of each subsystem equals the information stored in the rest of the universe, combining entanglement generation and decoherence into a single information budget. The paper also establishes a classical-channel dichotomy. A measure-and-feedforward channel calibrated to reproduce the same interaction produces no entanglement, while introducing additional noise. This provides an exact solvable distinction between a genuinely quantum mediator and a classical communication channel. The causal structure of mediation is studied in a multi-mode chain, where entanglement appears only after the mediator excitation reaches the relevant region, establishing a finite propagation constraint in the model. The work also proves analytically the separability boundary for partially coherent sources, including the condition relating source coherences required for entanglement generation. The results provide an exactly solvable framework connecting gravitationally induced entanglement, mediator quantum information, which-path records, decoherence, and quantum versus classical mediation. The declared limits are finite models, linear mediator coupling, and no claim of a complete theory of dynamical quantum gravity. Verification and reproducibility materials are included.

Gautam Gangopadhyay, S. H. Lin

We have shown that the Jaynes-Cummings model (JCM) with an environment-induced pure decoherence is an exactly solvable problem. Rabi oscillation of atomic population inversion and oscillation in the field population get trapped due to decoherence. But the decay of the coherence properties of the atom as well as of the field is comparatively slower than that of the population terms. It is also shown that although the fast oscillation in nonclassical properties are suppressed due to decoherence but an initial Poissonian field acquires a sub-Poissonian character in the steady state. So unlike the ordinary spontaneous emission all the nonclassical properties of the system are not erased.