2013/03/31 by Y. Liu, Frédéric Piéchon, F. Piechon +2
Computer Science · Mathematics · Physics and Astronomy · #Atomic and Subatomic Physics Research #Condensed matter physics #Dephasing #Exchange interaction #Ferromagnetism #Magnetic field #Mathematics #Nonlinear Dynamics and Pattern Formation #Physics #Quantum #Quantum dynamics #Quantum mechanics #Quantum optics and atomic interactions #Quantum phase transition #Spin (aerodynamics) #Spins #Statistical physics #Synchronization (alternating current) #Topology (electrical circuits) #cond-mat.quant-gas #quant-ph
paper · pdf · doi:10.1209/0295-5075/103/17007
published as Europhysics Letters 103, 17007 (2013) · 6 pages, 12 figures
arxiv created 2013/06/07 · openalex publication_date 2013/07/01 · arxiv updated 2013/07/24 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Motivated by the spin self-rephasing recently observed in an atomic clock, we introduce a simple dynamical model to study the competition between dephasing and synchronization. Two spins S are taken to be initially parallel and in the plane perpendicular to an inhomogeneous magnetic field Δ that tends to dephase them. In addition, the spins are coupled by exchange interaction J that tries to keep them locked. The analytical solution of the classical dynamics shows that there is a phase transition to a synchronized regime for sufficiently large exchange interaction compared to the inhomogeneity. The quantum dynamics is solved analytically in four limits —large/small and large/small S — and numerically in between. In sharp contrast to the classical case, the quantum solution features very rich S -dependent multiscale dynamics. For any finite S , there is no synchronization but a crossover around between two regimes. The synchronization transition is only recovered when , approaching the classical solution in a non-trivial way. Quantum effects therefore suppress the synchronization transition.