Quantum many-body spin ratchets

التفاصيل البيبلوغرافية
العنوان: Quantum many-body spin ratchets
المؤلفون: Zadnik, Lenart, Ljubotina, Marko, Krajnik, Žiga, Ilievski, Enej, Prosen, Tomaž
سنة النشر: 2024
المجموعة: Condensed Matter
Quantum Physics
مصطلحات موضوعية: Condensed Matter - Statistical Mechanics, Quantum Physics
الوصف: Introducing a class of SU(2) invariant quantum unitary circuits generating chiral transport, we examine the role of broken space-reflection and time-reversal symmetries on spin transport properties. Upon adjusting parameters of local unitary gates, the dynamics can be either chaotic or integrable. The latter corresponds to a generalization of the space-time discretized (Trotterized) higher-spin quantum Heisenberg chain. We demonstrate that breaking of space-reflection symmetry results in a drift in the dynamical spin susceptibility. Remarkably, we find a universal drift velocity given by a simple formula which, at zero average magnetization, depends only on the values of SU(2) Casimir invariants associated with local spins. In the integrable case, the drift velocity formula is confirmed analytically based on the exact solution of thermodynamic Bethe ansatz equations. Finally, by inspecting the large fluctuations of the time-integrated current between two halves of the system in stationary maximum-entropy states, we demonstrate violation of the Gallavotti-Cohen symmetry, implying that such states cannot be regarded as equilibrium ones. We show that the scaled cumulant generating function of the time-integrated current instead obeys a generalized fluctuation relation.
Comment: 23 pages, 3 figures
نوع الوثيقة: Working Paper
URL الوصول: http://arxiv.org/abs/2406.01571
رقم الأكسشن: edsarx.2406.01571
قاعدة البيانات: arXiv