Related papers: Conservation of angular momentum on a single-photo…
The past decades have seen substantial interest in the so-called orbital angular momentum (OAM) of light, driven largely by its diverse range of applications. However, there are fundamental theoretical issues with decomposing the angular…
Optical angular momentum (OAM) in light beams is manifested as the two-dimensional spatial distribution of its complex amplitude, necessitating a 2D detector for its measurement. Here we present a novel speckle-based machine learning…
Light is the fundamental medium through which we perceive the world around us. In the modern era, light can not only be used in its raw form but can also be used as a versatile tool. Generally, light fields carry energy and momentum (both…
Vortex $\gamma$ photons carrying orbital angular momenta (OAM) hold great potential for various applications. However, their generation remains a great challenge. Here, we successfully generate sub-MeV vortex $\gamma$ photons via…
High-dimensional entangled states in orbital angular momentum (OAM) basis offer several unique advantages for quantum information applications. However, for the optimal performance of a given application, one requires a generation technique…
We numerically and experimentally show that all photons generated by spontaneous parametric down-conversion (SPDC) follow a transverse amplitude similar to that of the pump. This amplitude transfer from pump to SPDC is revealed in the…
The transverse orbital angular momentum (OAM) of spatiotemporal optical vortices (STOVs) has been a topic of active debate in recent years. Previous studies, relying on narrowband and paraxial approximations, resulted in unprecedented…
We model spontaneous parametric down-conversion (SPDC) as classical difference frequency generation (DFG) of the pump field and a hypothetical stochastic "vacuum" seed field. We analytically show that the second-order spatiotemporal…
Detailed investigations of single photon 1st-order interferences of separated emitters allow for analyzing the role of the mode function in quantum optics. In an earlier Young's double slit experiment using a higher spatial light mode some…
We demonstrate polarization-entangled biphotons in a cold-atom double-$\Lambda$ system, overcoming atomic selection rules that suppress polarization correlations and favor orbital angular momentum (OAM) entanglement. Using spatial light…
The self-imaging, or Talbot Effect, that occurs with the propagation of periodically structured waves has enabled several unique applications in optical metrology, image processing, data transmission, and matter-wave interferometry. In this…
Orbital angular momentum (OAM) of light represents a fundamental optical freedom that can be exploited to manipulate quantum state of atoms. In particular, it can be used to realize spin-orbital-angular-momentum (SOAM) coupling in cold…
The atom-photon entanglement using the Laguerre-Gaussian beams is studied in the closed-loop three-level $V$-type quantum systems. We consider two schemes with degenerated and non-degenerated upper levels: in the first, the effect of the…
In this paper the coherence and crossing symmetry of the electromagnetic interaction of photons involved in the spontaneous parametric down conversion (SPDC) phenomena in nonlinear crystals, are investigated. On this basis a new…
Although solid-state platforms underpin modern electronics, little is known about how intense ultrashort light pulses carrying orbital angular momentum (OAM) interact with solids. This gap persists even though, for more conventional…
Spontaneous parametric down-conversion in quantum optics is an invaluable resource for the realization of high-dimensional qudits with spatial modes of light. One of the main open challenges is how to directly generate a desirable qudit…
We study the evolution of an orbital angular momentum (OAM) entangled bipartite photonic state for the case where one of the photons propagates through Kolmogorov turbulence, using the concurrence as a measure of entanglement. Quantum state…
Orbital angular momentum (OAM) recognition of vortex beams is critical for applications ranging from optical communications to quantum technologies. However, conventional approaches designed for free-space propagation struggle when light…
Recently, photons have been observed to possess transverse orbital angular momentum (OAM); however, it is unclear as whether they can hold a transverse OAM higher than 1. Here, we theoretically and experimentally demonstrate that high-order…
Scattering of non-classical light is enabling new ways to study and control photon transport. However, advances in this field often rely on simplifying assumptions regarding the quantum light's generation and its source. In this work, we…