Trace-class spectra of irreducible Gaussian quantum Markov semigroups
- URL: http://arxiv.org/abs/2609.06957v1
- Date: Mon, 07 Sep 2026 02:53:41 GMT
- Title: Trace-class spectra of irreducible Gaussian quantum Markov semigroups
- Abstract summary: For stable drift, irreducibility is equivalent to the existence of a unique faithful normal invariant state.<n>For periodic critical drift, we obtain an explicit spectral formula that includes the displacement and yields horizontal half-lines or parabolic regions.
- Score: 4.519380970399272
- License: http://creativecommons.org/licenses/by/4.0/
- Abstract: We determine the spectrum of the predual generator of an irreducible Gaussian quantum Markov semigroup on the trace-class operators over a finite-mode bosonic Fock space in the stable, strictly unstable, and periodic critical drift regimes. For stable drift, irreducibility is equivalent to the existence of a unique faithful normal invariant state. The spectrum and approximate point spectrum are the closed left half-plane, whereas the point spectrum is the open left half-plane together with zero. Thus the polynomial eigenvalues generated by the drift matrix do not exhaust the trace-class point spectrum. If the drift has an eigenvalue with strictly positive real part, the spectrum is again the closed left half-plane, but the point spectrum is empty and the open left half-plane together with zero belongs to the residual spectrum. For periodic critical drift, we obtain an explicit spectral formula that includes the displacement parameter and yields horizontal half-lines or parabolic regions. The proofs use characteristic functions, Gaussian diffusion semigroups, and bounded eigenoperators of the dual semigroup. The nonperiodic critical drift case remains open.
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