Quantum entropy and its applications in biophotonics

Jean‐Pierre Wolf

Alexei V. Sokolov, Jizhou Wang, Richard G. Sprague +4 more

Qiao Gu

Based on the elucidation for definition of entropy,we present a general method for calculating entropy of a quantum system in mixed state and apply it to the radiation fields in the typically mixed states.The results demonstrate that the quantum entropy is correlated to the microscopic fluctuation of the radiation fields,and it may therefore describe the quantum coherence properties of the radiation fields.As an example,the evolution of entropy of a dissipative quantum system is investigated then.The results obtained in this paper are expected to provide a basis for applications of entropy method in some fields,such as quantum optics,quantum informatics,biophotonics,and related interdisciplinary science.

Qiao Gu

The maximum entropy principle discovered by Jaynes E T governs a search of the most reasonable probability assignment of stochastic variable,based on the measured data.One of the simplest applications of this principle lies in that all the thermodynamical relations are derived from the maximizing entropy of the system with energy as a single measured value.The maximum entropy principle is used then for the radiation field as a quantum system.Our results show that with an increase of the number of measurable quantities,the thermal field,the coherent states as well as the squeezed states are automatically introduced in turn;in particular,the dependence of all the properties of these radiation fields on the thermal noise is formulated quantitatively.The fundamental results obtained in this paper are expected to provide a basis for applications of the maximum entropy principle in some fields,such as quantum optics,quantum informatics,biophotonics,and related interdisciplinary science.

Simon J. D. Phoenix

Masanori Ohya, Dėnes Petz