Nepomechie, Rafael IGuan, Xi-Wen2020-06-15http://hdl.handle.net/1885/205084We consider the problem of a central spin with arbitrary spin s that interacts pairwise and uniformly with a bath of N spins with s = 1/2. We present two approaches for determining the exact spectrum of this model, one based on properties of SU(2), and the other based on integrability. We also analyze the exact time evolution of a spin coherent state, and compute the time evolution of various quantities of physical interest, including the entanglement entropy, spin polarization and Loschmidt echo.20 pagesapplication/pdfen-AU© 2018 IOP Publishing Ltd and SISSA Medialab srlintegrable spin chains and vertex models, quantum dots, quantum integrability (Bethe ansatz)2018-10-2410.1088/1742-5468/aae2d92019-12-22