Dresden 2020 – wissenschaftliches Programm
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TT 33.9: Vortrag
Mittwoch, 18. März 2020, 11:45–12:00, HSZ 201
Quantum Dynamics Made Fast: Achieving Linear Time-Scaling for Nonequilibrium Green Functions — •Niclas Schlünzen, Jan-Philip Joost, and Michael Bonitz — CAU Kiel, Germany
The accurate description of nonequilibrium dynamics in correlated quantum-many-body systems remains to be a driving force for current research in condensed-matter physics and beyond. Among others, the nonequilibrium Green functions (NEGF) method has proven to be a powerful tool to predict quantum dynamics. However, NEGF simulations are computationally expensive due to their T3 scaling with the simulation duration T . With the introduction of the generalized Kadanoff–Baym ansatz (GKBA), T2 scaling could be achieved for second order Born (SOA) selfenergies, which has substantially extended the scope of NEGF simulations. Recently, we could show that GKBA-NEGF simulations can be performed with order T1 scaling for SOA and even GW selfenergies. Here, we show numerical results for various many-body approximations and demonstrate that tremendous computational speed-up can be achieved.
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