{ "id": "2301.06255", "version": "v1", "published": "2023-01-16T04:30:06.000Z", "updated": "2023-01-16T04:30:06.000Z", "title": "Stability of time-periodic $\\mathcal{PT}$ and anti-$\\mathcal{PT}$-symmetric Hamiltonians with different periodicities", "authors": [ "Julia Cen", "Yogesh N. Joglekar", "Avadh Saxena" ], "categories": [ "quant-ph" ], "abstract": "Hermitian Hamiltonians with time-periodic coefficients can be analyzed via Floquet theory, and have been extensively used for engineering Floquet Hamiltonians in standard quantum simulators. Generalized to non-Hermitian Hamiltonians, time-periodicity offers avenues to engineer the landscape of Floquet quasi-energies across the complex plane. We investigate two-level non-Hermitian Hamiltonians with coefficients that have different periodicities using Floquet theory. By analytical and numerical calculations, we obtain their regions of stability, defined by real Floquet quasi-energies, and contours of exceptional point (EP) degeneracies. We extend our analysis to study the phases that accompany the cyclic changes. Our results demonstrate that time-periodic, non-Hermitian Hamiltonians generate a rich landscape of stable and unstable regions.", "revisions": [ { "version": "v1", "updated": "2023-01-16T04:30:06.000Z" } ], "analyses": { "keywords": [ "symmetric hamiltonians", "periodicities", "floquet theory", "real floquet quasi-energies", "two-level non-hermitian hamiltonians" ], "note": { "typesetting": "TeX", "pages": 0, "language": "en", "license": "arXiv", "status": "editable" } } }