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We present a numerical study of the spatial coherence of light that is radiated from a dilute ensemble of atoms. The spatial coherence is established as a result of the collective (cooperative) coupling of the atoms to the light, and is…

Quantum Physics · Physics 2025-05-27 Deniz Yavuz , Anirudh Yadav , David Gold , Thad Walker , Mark Saffman

Fluctuations in light absorption by atoms are observed by applying laser light on rubidium atoms and measuring the transmitted light intensity fluctuations. These fluctuations are spontaneous noise, which are generic to photon atom…

Atomic Physics · Physics 2015-06-12 Takahisa Mitsui , Kenichiro Aoki

Shadowing is a quantum phenomenon leading to a non-additivity of electroweak cross sections on nucleons bound in a nucleus. It occurs due to destructive interference of amplitudes on different nucleons. Although the current experimental…

High Energy Physics - Phenomenology · Physics 2012-11-26 B. Z. Kopeliovich , J. G. Morfin , Ivan Schmidt

The radiation forces on a Rayleigh dielectric sphere induced by a partially coherent light beam are greatly affected by the coherence of the light beam. The magnitude of the radiation forces on a dielectric sphere near the focus point…

Optics · Physics 2009-11-13 Li-Gang Wang , Cheng-Liang Zhao , Li-Qin Wang , Xuan-Hui Lu , Shi-Yao Zhu

The use of a wire mesh facilitates creation of multiple optical traps for manipulation of small micron or sub-micron particles. Such an array of optical traps can be easily controlled. The trap that is formed in this manner is a continuous…

Optics · Physics 2007-05-23 J. A. Dharmadhikari , A. K. Dharmadhikari , D. Mathur

Laser-plasma technology promises a drastic reduction of the size of high energy electron accelerators. It could make free electron lasers available to a broad scientific community, and push further the limits of electron accelerators for…

An atom laser is a hypothetical device which would produce an atomic field analogous to the electromagnetic field of a photon laser. Here I argue that for this analogy to be meaningful it is necessary to have a precise definition of a laser…

Quantum Physics · Physics 2007-05-23 Howard M. Wiseman

Emitting light towards on-demand directions is important for various optoelectronic applications, such as optical communication, displaying, and ranging. However, almost all existing directional emitters are assemblies of passive optical…

We demonstrate that there is a fundamental limit to the sensitivity of phase-based detection of atoms with light for a given maximum level of allowable spontaneous emission. This is a generalisation of previous results for two-level and…

Quantum Physics · Physics 2009-11-10 J. J. Hope , J. D. Close

Diffraction limits the behaviour of light in optical systems and sets the smallest achievable line width at half the wavelength. With a novel subwavelength plasmonic lens to reduce the diffraction via an asymmetry and to generate and…

Optics · Physics 2009-01-30 K. R. Chen

We analyze the quantum properties of the light generated by a two-level laser in which the two-level atoms available in a closed cavity are pumped to the upper level by means of electron bombardment. We consider the case in which the…

Quantum Physics · Physics 2015-06-11 Fesseha Kassahun

We theoretically and experimentally demonstrate the focusing of macroscopic 3D darkness surrounded by all light in free space. The object staying in the darkness is similar to staying in an empty light capsule because light just bypasses it…

Laser communication has advances in compared with radio frequency communication as result of much high carrier frequency from ultraviolet to near infrared. Very narrow laser beam is possible to form with very high power density. But laser…

Instrumentation and Methods for Astrophysics · Physics 2017-11-30 Volodymyr Kuzkov , Sergii Kuzkov , Serhii Borysenko

When a light bulb is turned on, light moves away from it at speed $c$, by definition. When light from this bulb illuminates a surface, however, this illumination front is not constrained to move at speed $c$. A simple proof is given that…

Popular Physics · Physics 2016-06-22 Robert J. Nemiroff , Qi Zhong , Elias Lilleskov

Due to high exploitation costs and other environmental issues, it would be desirable to phase out large cinema projection systems based on standard xenon lamps in favor of laser based projection devices. Lasers provide longer lifetime and…

Applied Physics · Physics 2018-03-20 Pierre Walczak , Xavier Hachair , Stéphane Barland

Theoretical studies of superradiant lasing on optical clock transitions predict a superb frequency accuracy and precision closely tied to the bare atomic linewidth. Such a superradiant laser is also robust against cavity fluctuations when…

Quantum Physics · Physics 2021-11-02 Anna Bychek , Christoph Hotter , David Plankensteiner , Helmut Ritsch

We discuss the main features of a new optical system capable of laser action: the active complex optical network, or lasing network (LANER). The system is experimentally realized with optical fibers linked each other with suitable optical…

Optics · Physics 2019-02-27 Giovanni Giacomelli , Stefano Lepri , Cosimo Trono

Optical forces allow manipulation of small particles and control of nanophotonic structures with light beams. Here, we describe a counter-intuitive lateral optical force acting on particles placed above a substrate, under uniform plane wave…

We develop an ab initio analytic theory of random lasing in an ensemble of atoms that both scatter and amplify light. The theory applies all the way from low to high density of atoms. The properties of the random laser are controlled by an…

Disordered Systems and Neural Networks · Physics 2015-03-19 A. Goetschy , S. E. Skipetrov

Atoms in a sub-wavelength lattices have remarkable optical properties that have become of high scientific and technological significance. Here, we show how the coupling of light to more than a single atomic array can expand these…

Quantum Physics · Physics 2023-03-31 Simon Panyella Pedersen , Lida Zhang , Thomas Pohl