Tunneling of bosonic qubits under local dephasing through a microscopic approach;
: Ferrara, Alberto; Nosrati, Farzam; Smirne, Andrea; Piilo, Jyrki; Lo Franco, Rosario
Publisher: American Physical Society (APS)
: 2026
Physical Review A
: 012415
: 114
: 1
: 2469-9926
: 2469-9934
DOI: https://doi.org/10.1103/f2sy-sj27
: https://doi.org/10.1103/f2sy-sj27
: https://research.utu.fi/converis/portal/detail/Publication/527028784
We present a microscopic derivation of a master equation for two-component bosons (bosonic qubits) which tunnel between spatially separated modes under local dephasing noise. Starting from the full system-bath Hamiltonian with Lorentzian coupling distributions, we analytically obtain a time-local master equation whose structure reveals intrinsic non-Markovian features and recovers the standard phenomenological dephasing model in the short-time limit. Comparison with exact pseudomode simulations confirms its validity beyond weak-coupling and Markovian regimes. We identify a resonance condition between tunneling and bath frequencies for which dephasing drives the system toward correlated steady states, stabilizing coherence and entanglement instead of suppressing them. These results establish a rigorous microscopic foundation for dephasing models in bosonic tunneling systems and reveal a noise-induced mechanism for steady-state entanglement.
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R.L.F. acknowledges support from Ministero dell'Università e della Ricerca (MUR) through PNRR Project ICON-Q, Partenariato Esteso NQSTI, Project No. PE00000023, Spoke 2, CUP J13C22000680006; PNRR Project QUANTIP, Partenariato Esteso NQSTI, Project No. PE00000023, Spoke 9, CUP E63C22002180006; and PNRR Project PRISM, Partenariato Esteso RESTART, Project No. PE00000001, Spoke 4, CUP C79J24000190004. A.S. acknowledges support from MUR and Next Generation EU via the PRIN 2022 Project “Quantum Reservoir Computing (QuReCo)” (Contract No. 2022FEXLYB) and the NQSTI-Spoke1-BaC project QSynKrono (Contract No. PE00000023-QuSynKrono). F.N. acknowledges support by the I+D+i project MADQuantum-CM, financed by the European Union NextGeneration-EU, Madrid Government and by the PRTR. A.F. would like to thank Matteo Piccolini for a critical reading of the manuscript and Nicola Macrì for useful discussions.
