Bose-Hubbard lattice as a controllable environment for open quantum systems

Abstract

We investigate the open dynamics of an atomic impurity embedded in a one-dimensional Bose-Hubbard lattice. We derive the reduced evolution equation for the impurity and show that the Bose-Hubbard lattice behaves as a tunable engineered environment allowing one to simulate both Markovian and non-Markovian dynamics in a controlled and experimentally realizable way. We demonstrate that the presence or absence of memory effects is a signature of the nature of the excitations induced by the impurity, being delocalized or localized in the two limiting cases of a superfluid and Mott insulator, respectively. Furthermore, our findings show how the excitations supported in the two phases can be characterized as information carriers.

Pulsed Generation of Quantum Coherences and Non-classicality in Light-Matter Systems

“…Thus our results should also be of interest for temporal control schemes in practical quantum information processing and quantum computation. On a more fundamental level, our results may be helpful for the development of an open-dynamics quantum simulator, for shedding new light on core issues at the foundations of physics, including the quantum-to-classical transition and quantum measurement theory [218], and characterization of Markovianity in quantum systems [112,219,220]. Our findings could also help shed light on system-environment entanglement, if we view the matter subsystem as the system of interest and the radiation subsystem as the environment, and if the system-environment interaction is chosen to be a sequence of pulses with different correlation properties.…”

“…More recently, there has been a surge of theoretical and experimental interest in temporal, in addition to spatial, quantum correlations. First, in some scenarios nonlocal measurements are quite challenging, and thus local measurements such as STC can be used instead to access the underlying physics [69,70,71,72,111,112]. Second, STC are key quantities to understand the phenomenology and control mechanisms of strongly correlated systems in and out of equilibrium [113,114,115,116,117,118].…”

“…The potential richness of effects in this intermediate case and in the regime of non-static coupling, is therefore of significant interest for temporal quantum control in practical quantum information processing and quantum computation. On a more fundamental level, an open-dynamics quantum simulator would be invaluable for shedding new light on core issues at the foundations of physics, ranging from the quantum-to-classical transition and quantum measurement theory [218] to the characterization of Markovian and non-Markovian systems [112,219,220].…”

Floquet stroboscopic divisibility in non-Markovian dynamics

“…. Possible directions in the future include the theoretical investigation of environments that exhibit phase transitions [47], dissipative phase transitions [48] and a time-nonlocal master equations [49]. numbers from quantum processes"); and travel support by the EU IP-SIQS.…”

Impurity dephasing in a Bose-Hubbard model

“…However, when the environment is strongly correlated or non-harmonic, the above picture may no longer be accurate and more involved approaches are required to account for the resulting non-Gaussian environment statistics. The state-of-the-art methods to numerically study these systems are based on matrix-product states [15][16][17][18]; nevertheless, due to the rapid entanglement growth, these methods become highly inefficient beyond one-dimensional cases or when approaching to a critical regime.…”