关键词: 量子失谐, 非X-型量子态, 解析解

Abstract: The concept of quantum discord was firstly proposed by Olliver and Zurek in 2001. It is a very important quantum correlation between quantum states except quantum entanglement. The analytical calculation of quantum discord between qubits is often very complicated, so the calculation of the quantum discord is mainly for the X-states, the studies for the non-X-states are very few. We presented analytical formulae of a class of non-X-states with five parameters based on Von Neumann entropy and classical correlation. We converted the formulea into a univariate function and used the monotonicity of the function to derive its analytical explicit formula. We found that the quantum discord can be computed in this way for a known two qubits.

Key words: quantum discord, non-X-state, analytical solution