This book details parametric down-conversion for the generation of non-classical state of light and its applications in generating various kinds of quantum entanglement among multiple photons from parametric down-conversion. It presents applications of the principle of quantum interference to multi-photon systems. The book also details continuous variable entanglement and various types of multi-photon interference effects.

This collection of lectures covers a wide range of present day research in thermodynamics and the theory of phase transitions far from equilibrium. The contributions are written in a pedagogical style and present an extensive bibliography to help graduates organize their further studies in this area. The reader will find lectures on principles of pattern formation in physics, chemistry and biology, phase instabilities and phase transitions, spatial and temporal structures in optical systems, transition to chaos, critical phenomena and fluctuations in reaction-diffusion systems, and much more.

Superposition principle is one of the most challenging principles of quantum theory, especially in the multi-particle situation. In the language of quantum mechanics, the high-order quantum interference of multi-particle is the consequence of a superposition among different yet indistinguishable probability amplitudes, a non-classical entity corresponding to different yet indistinguishable alternative ways of producing a joint-detection event among distant detectors. In optics, the theory of multiphoton interference of quantum light such as entangled photons are well established and accepted. On the other hand, classical interpretation is frequently used to explain the multiphoton interference of classical light such as thermal light and pseudo-thermal light due to the historical reasons. In this dissertation, we will focus on the study of high-order interference of photons in thermal and pseudo-thermal states. Sunlight, as a typical thermal light, contains a large number of independent and randomly radiated point subsources resulted from the spontaneous atomic transitions. The atomic transitions emit subfields at random positions and times with random phases. The pseudo-thermal light, consisting of a laser beam and a rotating diffusing ground glass, which is frequently used in the lab, can also be modeled as containing a large number of independent and randomly radiated subsouces. A large number of subelds with random phases are then generated from those subsources at random positions and times. As we will show in the dissertation, despite the classical feature of the source, the high-order interference of photons in thermal and pseudo-thermal states can only be fully understood by quantum theory due to the nonlocal nature. We gave a new analysis of the statistical property of pseudo-thermal light based on the coherent state representation following the Glauber-Scully theory. We showed that the new model can describe the energy distribution of the pseudo-thermal light very well. We then showed a novel detection scheme called Photon-Number Fluctuation Correlation(PNFC) protocol, which measures the photon number fluctuation of each of the photodetectors and calculates the statistical correlation between them. This scheme was then applied to measure a 100% HBT correlation and the result can be explained as a nonlocal two-photon interference phenomenon. In additional, the PNFC protocol can be applied to thermal light ghost imaging resulting a 100% visibility ghost imaging measurement as well as high resolution. A set of experiments on the foundations of quantum theory including the delayed-choice quantum eraser experiment and Popper's experiment are then discussed. Nonlocal interference of randomly paired photons measured with the PNFC protocol is applied to explain the experimental results. The single photon picture can lead to paradoxes that can only be understood with the nonlocal interference of random thermal photon pairs with themselves. The nonlocal feature in the interference of photons in thermal state then inspired us to simulate Bell sate with photons in thermal state and extended the test of Bell s inequality to the fluctuation correlation measurement. Experimental observation of Bell correlation from the polarization measurement of thermal fields in photon-number fluctuations is reported, the experimental test of Bell's inequality in photon-number fluctuations is also reported. We then extended this scheme to the simulation of 3-photon GHZ state. The successful simulation of n-photon entangled states can lead to new perspective for quantum computing with thermal light. To demonstrate the potential of thermal light quantum computing, a simulation of the controlled-NOT gate operation is shown in the last part of the thesis. Throughout the dissertation, we showed that the phenomena of photons in thermal and pseudo-thermal state can be more easily and deeply understood by quantum mechanics.

Light and light based technologies have played an important role in transforming our lives via scientific contributions spanned over thousands of years. In this book we present a vast collection of articles on various aspects of light and its applications in the contemporary world at a popular or semi-popular level. These articles are written by the world authorities in their respective fields. This is therefore a rare volume where the world experts have come together to present the developments in this most important field of science in an almost pedagogical manner. This volume covers five aspects related to light. The first presents two articles, one on the history of the nature of light, and the other on the scientific achievements of Ibn-Haitham (Alhazen), who is broadly considered the father of modern optics. These are then followed by an article on ultrafast phenomena and the invisible world. The third part includes papers on specific sources of light, the discoveries of which have revolutionized optical technologies in our lifetime. They discuss the nature and the characteristics of lasers, Solid-state lighting based on the Light Emitting Diode (LED) technology, and finally modern electron optics and its relationship to the Muslim golden age in science. The book’s fourth part discusses various applications of optics and light in today's world, including biophotonics, art, optical communication, nanotechnology, the eye as an optical instrument, remote sensing, and optics in medicine. In turn, the last part focuses on quantum optics, a modern field that grew out of the interaction of light and matter. Topics addressed include atom optics, slow, stored and stationary light, optical tests of the foundation of physics, quantum mechanical properties of light fields carrying orbital angular momentum, quantum communication, and Wave-Particle dualism in action.

Galileo Unbound traces the journey that brought us from Galileo's law of free fall to today's geneticists measuring evolutionary drift, entangled quantum particles moving among many worlds, and our lives as trajectories traversing a health space with thousands of dimensions. Remarkably, common themes persist that predict the evolution of species as readily as the orbits of planets or the collapse of stars into black holes. This book tells the history of spaces of expanding dimension and increasing abstraction and how they continue today to give new insight into the physics of complex systems. Galileo published the first modern law of motion, the Law of Fall, that was ideal and simple, laying the foundation upon which Newton built the first theory of dynamics. Early in the twentieth century, geometry became the cause of motion rather than the result when Einstein envisioned the fabric of space-time warped by mass and energy, forcing light rays to bend past the Sun. Possibly more radical was Feynman's dilemma of quantum particles taking all paths at once — setting the stage for the modern fields of quantum field theory and quantum computing. Yet as concepts of motion have evolved, one thing has remained constant, the need to track ever more complex changes and to capture their essence, to find patterns in the chaos as we try to predict and control our world.

Femtosecond laser micromachining of transparent material is a powerful and versatile technology. In fact, it can be applied to several materials. It is a maskless technology that allows rapid device prototyping, has intrinsic three-dimensional capabilities and can produce both photonic and microfluidic devices. For these reasons it is ideally suited for the fabrication of complex microsystems with unprecedented functionalities. The book is mainly focused on micromachining of transparent materials which, due to the nonlinear absorption mechanism of ultrashort pulses, allows unique three-dimensional capabilities and can be exploited for the fabrication of complex microsystems with unprecedented functionalities.This book presents an overview of the state of the art of this rapidly emerging topic with contributions from leading experts in the field, ranging from principles of nonlinear material modification to fabrication techniques and applications to photonics and optofluidics.