{ "id": "1403.4204", "version": "v2", "published": "2014-03-17T18:39:53.000Z", "updated": "2014-08-28T23:56:27.000Z", "title": "PT-symmetry breaking with divergent potentials: lattice and continuum cases", "authors": [ "Yogesh N. Joglekar", "Derek D. Scott", "Avadh Saxena" ], "comment": "Revised text", "categories": [ "quant-ph", "physics.optics" ], "abstract": "We investigate the parity- and time-reversal ($\\mathcal{PT}$)-symmetry breaking in lattice models in the presence of long-ranged, non-hermitian, $\\mathcal{PT}$-symmetric potentials that remain finite or become divergent in the continuum limit. By scaling analysis of the fragile $\\mathcal{PT}$ threshold for an open finite lattice, we show that continuum loss-gain potentials $V_\\alpha(x)\\propto i |x|^\\alpha \\mathrm{sign}(x)$ have a positive $\\mathcal{PT}$-breaking threshold for $\\alpha>-2$, and a zero threshold for $\\alpha\\leq -2$. When $\\alpha<0$ localized states with complex (conjugate) energies in the continuum energy-band occur at higher loss-gain strengths. We investigate the signatures of $\\mathcal{PT}$-symmetry breaking in coupled waveguides, and show that the emergence of localized states dramatically shortens the relevant time-scale in the $\\mathcal{PT}$-symmetry broken region.", "revisions": [ { "version": "v1", "updated": "2014-03-17T18:39:53.000Z", "comment": "6 pages, 4 figures", "journal": null, "doi": null }, { "version": "v2", "updated": "2014-08-28T23:56:27.000Z" } ], "analyses": { "subjects": [ "11.30.Er", "42.82.Et" ], "keywords": [ "divergent potentials", "continuum cases", "pt-symmetry breaking", "symmetry broken region", "higher loss-gain strengths" ], "tags": [ "journal article" ], "publication": { "doi": "10.1103/PhysRevA.90.032108", "journal": "Physical Review A", "year": 2014, "month": "Sep", "volume": 90, "number": 3, "pages": "032108" }, "note": { "typesetting": "TeX", "pages": 6, "language": "en", "license": "arXiv", "status": "editable", "adsabs": "2014PhRvA..90c2108J" } } }