Integrable multistate Landau-Zener models with parallel energy levels

• URL: http://arxiv.org/abs/2001.10091v3
• Date: Thu, 25 Jun 2020 23:28:49 GMT
• Title: Integrable multistate Landau-Zener models with parallel energy levels
• Authors: Vladimir Y. Chernyak, Fuxiang Li, Chen Sun, and Nikolai A. Sinitsyn
• Abstract summary: solvable multistate Landau-Zener (MLZ) models whose Hamiltonians have commuting partner operators with $sim 1/tau$-time-dependent parameters. We derive the integrability conditions on the parameters of such commuting operators, and demonstrate how to use such conditions in order to derive new solvable cases.
• Score: 5.3908827521850196
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: We discuss solvable multistate Landau-Zener (MLZ) models whose Hamiltonians have commuting partner operators with $\sim 1/\tau$-time-dependent parameters. Many already known solvable MLZ models belong precisely to this class. We derive the integrability conditions on the parameters of such commuting operators, and demonstrate how to use such conditions in order to derive new solvable cases. We show that MLZ models from this class must contain bands of parallel diabatic energy levels. The structure of the scattering matrix and other properties are found to be the same as in the previously discussed completely solvable MLZ Hamiltonians.

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