Indistinguishability of Temporally Separated Pairwise Two- Photon State of Thermal Photons in Franson-Type Interferometry

The phenomenon of Franson interference with time–energy entangled photon pairs beyond the single-photon coherence length observed upon nonlocal measurement at two space-like separated locations is of particular research interest. Herein, we determine the coherence length of temporally separated pairwise two-photon (TSPT) states of thermal photons emitted from a warm atomic ensemble in Franson-type interferometry, with the setup consisting of two spatially separated unbalanced Michelson interferometers beyond the coherence length of a thermal photon. Using a novel method of square-modulated thermal photons, we show that the sinusoidal Franson-type interference fringe of thermal photons is determined by the presence or absence of TSPT states (corresponding to the time delay between the long and short paths in Franson-type interferometry). We find that the indistinguishability of the TSPT state in the Franson-type interference is independent of the temporal separation of the thermal photons in the TSPT states.

Investigation of partially transparent and high-density two-phase liquids using laser interference method

The purpose of the present work was to investigate partially transparent and high-density two-phase liquids using the laser interference method to establish the limits of applicability of this method. The results of the work include the interference fringe patterns of drops when using various kinds of liquids, the calculated drop sizes. The calculation of inaccuracies was also carried out to further establishing the limits of applicability of this method.

A Low-rank Approach to Image Defringing

In this work, we revisit the problem of interference fringe patterns in CCD chips occurring in near-infrared bands due to multiple light reflections within the chip. We briefly discuss the traditional approaches that were developed to remove these patterns from science images, and mention their limitations. We then introduce a new method to globally estimate the fringe patterns in a collection of science images without additional external data, allowing for some variation of the patterns between images. We demonstrate this new method on near-infrared images taken by the CFHT wide-field imager Megacam.

Light Strands not Wave Interference: Clarification of the Double Slit Experiment

Objective Modern understanding of light has fluctuated between particle and wave theory. The classic double slit experiment provided crucial support of wave theory with its description of wave interference fringe patterns. To our knowledge, no significant study has been performed on light propagation in free space after exiting the slit. To further understand the double slit results we analyzed light behavior in free space using novel visualization techniques.Methods A micro-particle environment was developed that remained transparent to visible light. Coherent light was observed in this environment in settings of diffraction, refraction, and reflection.Results Experimental generation of distinct light strands after diffraction through double slits is visualized. Definitive images of discrete light strands, not waves, were noted as light propagated through free space. Light strands were visualized directly creating the pseudo-interference fringe pattern, refuting the concept of wave interference.Conclusions Novel generation and visualization of light strands confirms the particle theory of light and counters two hundred years of wave doctrine. The finding that diffractive fringe patterns and other observations of light are due to the phenomena of discrete radiating strands, not wave interference, will have implications in physics, quantum mechanics, and technology.