Osamu Hirota
Tamagawa University, Japan
Title: Importance and applications of infinite dimensional non-orthogonal quantum state
Biography
Biography: Osamu Hirota
Abstract
Non-orthogonal quantum states in infinite dimensional space are playing a special role in foundation of quantum mechanics. The Gaussian state is a typical example of such a state that was considered at beginning of history of quantum theory. The explicit importance of Gaussian quantum states such as coherent state was certified by R Glauber, ECG Sudarshan et al in quantum optics for understanding a nature of laser. More progress has been given by H P Yuen who discovered a special property of generalized coherent state known as squeezed state and a method to verify them experimentally. Then current interest goes to entanglement of non-orthogonal quantum state such as two-mode squeezed state and quasi-Bell entangled coherent state. On the other hand, a problem of discrimination of non-orthogonal quantum states through quantum measurement that was pioneered by C W Helstrom is also a foundation of quantum physics. Its basic criteria are Bayes, Neyman-Peason, and Minimax which play different roles. In this talk, I present a historical survey of importance of non-orthogonal quantum state, and progress of quantum state discrimination. Also I introduce potential applications of theoretical achievements on non-orthogonal quantum state such as Quantum Methodology and Quantum Enigma Cipher based on recent experimental progress.