Applications of optical coherence theory

Ayman F. Abouraddy

The statistical description of optical fields in coherence theory is based on underlying fluctuations originating at the source or during propagation through a random medium. We show that uncertainty (partial coherence) also stems from the act of ignoring a degree of freedom of a beam when observing another degree of freedom classically entangled with it. Specifically, we demonstrate that Bells measure, commonly used in tests of quantum non-locality, is as a quantitative tool that delineates intrinsic incoherence associated with statistical fluctuations from classical entanglement-based incoherence. This demonstrates, more generally, the applicability of concepts from quantum information processing to classical optical coherence theory and optical signal processing.

Tuguldur Begzjav

During the last half century, quantum coherence has been of great interest due to its own right and also due to its broad range of applications in many areas of physics. The reason for that is the technological progress made last century, specially, the invention of coherent light sources and their commercialization. Indeed, coherent laser sources allow us to coherently excite atoms and molecules, as a consequence, to study variety of coherent and collective phenomena in atomic physics, for instance, coherent optical spectroscopy, superradiance, superflourescence, lasing without inversion and so forth. Interestingly, recent studies in biological systems also seem to exhibit coherent processes, in particular, photosynthetic transport and avian compass.\n\nIn this dissertation, we present some of the theory and applications of the quantum coherence. This study considers (i) application of quantum coherence to enhance output signals of coherent anti-Stokes Raman spectroscopy of optically active media (chiral molecules), (ii) a way to find general formulas of single- and double-excited subradiant Dicke states using symmetry group theory, (iii) an impact of Fano-Agarwal coupling and other virtual processes arising from non-rotating wave approximation on the decay of super and subradiant timed Dicke states, and finally (iv) quantum coherence and collective phenomena of relativistically and uniformly accelerating atoms.\n\nApplications of the results presented in the dissertation may be a new method for resolving chirality of molecules using coherent anti-Stokes Raman spectroscopy - Raman optical activity, and a sidewise excitation method for single- and double-excited subradiant states. The obtained results also advance our theoretical understanding of quantum coherence specially theory of super and subradiance.

Daniel F. Walls, Gerard J Milburn

Kedar Khare, Mansi Butola, Sunaina Rajora

Si-Yuan 思远 Liu 刘, Heng 桁 Fan 范

Quantum coherence is a basic concept in quantum mechanics, representing one of the most fundamental characteristics that distinguishes quantum mechanics from classical physics. Quantum coherence is the basis for multi-particle interference and quantum entanglement. It is also the essential ingredient for various physical phenomena in quantum optics, quantum information, etc. In recent years, with the proposal of a quantum coherence measurement scheme based on a resource theory framework, quantum coherence as a quantum resource has been extensively investigated. This article reviews the resource theories of quantum coherence and introduces the important applications of quantum coherence in quantum computing, quantum information, and interdisciplinary fields, particularly in quantum thermodynamics and quantum biology. Quantum coherence and its applications are still being explored and developed. We hope this review can provide inspiration for relevant research.