表題番号：2019C-256
日付：2020/02/17

研究課題量子2準位系の解析解と量子論基礎

研究者所属（当時） | 資格 | 氏名 | |
---|---|---|---|

（代表者） | 理工学術院 先進理工学部 | 教授 | 中里 弘道 |

- 研究成果概要
- On the basis of the recent proposal for the new parametrization of evolution operators for quantum two-level systems, a protocol for explicitly constructing the exact evolution operators generated by 2×2 time-dependent PT-symmetric Hamiltonians is proposed. Its mathematical applicability is illustrated with the help of appropriate examples. The physical relevance of the proposed approach within gain-loss system scenarios, like two coupled waveguides, is discussed in detail. On the other hand, in the general framework of mixed states, an explicit bound for bipartite NPT entanglement is derived on the basis of the mixedness characterization of the physical system. The result derived is very general, being based only on the assumption of finite dimensionality. In addition it turns out to be of experimental interest since some purity measuring protocols are known. Exploiting the bound in the particular case of thermal entanglement, a way to connect thermodynamic features to monogamy of quantum correlations is suggested, and some recent results on the subject are given a physically clear explanation.