Dresden 2020 – wissenschaftliches Programm
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DY 31.10: Vortrag
Mittwoch, 18. März 2020, 12:00–12:15, HÜL 186
Long-lived coherence in driven spin systems: from two- to infinite spatial dimensions — •Walter Hahn and V. V. Dobrovitski — QuTech, Delft University of Technology, Lorentzweg 1, 2628 CJ Delft, The Netherlands
We study dipolar-coupled quantum many-spin systems with local disorder, subject to periodic pulse driving, in different spatial dimensions: from two-dimensional to (effectively) infinite-dimensional systems. Using direct numerical simulations, we show that these systems exhibit long-lived magnetization response for all dimensions, despite strong fluctuations in the spin-spin couplings, and corresponding strong singularities in the spin dynamics. We observe the long-lived magnetization response for the initial polarization being either along the driving pulses, or along the axis conserved by the internal Hamiltonian. For longer time delays, the magnetization echoes exhibit an even-odd asymmetry, i.e. the system's response is modulated at the period which is twice the period of the driving. The above results are corroborated by a Floquet-operator analysis.
This work was supported by Dutch Research Council (NWO) and by DARPA DRINQS program.