



02003nas a2200217   4500008004100000245007300041210006900114260001300183520129800196653002701494653003101521653004701552100002001599700002201619700002101641700001601662700001801678700002401696700002801720856003701748       2022                        eng d00aExperimental observation of thermalisation with noncommuting charges0 aExperimental observation of thermalisation with noncommuting cha  c2/9/20223 a<p>Quantum simulators have recently enabled experimental observations of quantum many-body systems&#39; internal thermalisation. Often, the global energy and particle number are conserved, and the system is prepared with a well-defined particle number - in a microcanonical subspace. However, quantum evolution can also conserve quantities, or charges, that fail to commute with each other. Noncommuting charges have recently emerged as a subfield at the intersection of quantum thermodynamics and quantum information. Until now, this subfield has remained theoretical. We initiate the experimental testing of its predictions, with a trapped-ion simulator. We prepare 6-15 spins in an approximate microcanonical subspace, a generalisation of the microcanonical subspace for accommodating noncommuting charges, which cannot necessarily have well-defined nontrivial values simultaneously. We simulate a Heisenberg evolution using laser-induced entangling interactions and collective spin rotations. The noncommuting charges are the three spin components. We find that small subsystems equilibrate to near a recently predicted non-Abelian thermal state. This work bridges quantum many-body simulators to the quantum thermodynamics of noncommuting charges, whose predictions can now be tested.</p>10aFOS: Physical sciences10aQuantum Physics (quant-ph)10aStatistical Mechanics (cond-mat.stat-mech)1 aKranzl, Florian1 aLasek, Aleksander1 aJoshi, Manoj, K.1 aKalev, Amir1 aBlatt, Rainer1 aRoos, Christian, F.1 aHalpern, Nicole, Yunger  uhttps://arxiv.org/abs/2202.04652