3 papers
quant-ph2025
Accelerated calculation of impurity Green's functions exploiting the extreme Mpemba effect
David J. Strachan, Archak Purkayastha, Stephen R. Clark
Simulating the dynamics of quantum impurity models remains a fundamental challenge due to the complex memory effects that arise from system-environment interactions. Of particular…
quant-ph2025
Schwinger-Keldysh non-perturbative field theory of open quantum systems beyond the Markovian regime: Application to spin-boson and spin-chain-boson models
Felipe Reyes-Osorio, Federico Garcia-Gaitan, David J. Strachan +3
We develop a unified framework for open quantum systems composed of many mutually interacting quantum spins, or any isomorphic systems like qubits and qudits, surrounded by one or…
quant-ph2024
Extracting Dynamical Maps of Non-Markovian Open Quantum Systems
David J. Strachan, Archak Purkayastha, Stephen R. Clark
The most general description of quantum evolution up to a time is a completely positive tracing preserving map known as a dynamical map . Here we consider $\hatÎ(…