English
Related papers

Related papers: Random Lasers for Broadband Directional Emission

200 papers

New, fundamental resonant properties of laser resonators are theoretically predicted and experimentally demonstrated. These resonances occur either in the time dependence of the beam width and that of beam radius of curvature of the…

Optics · Physics 2015-06-05 A. Kohazi-Kis , J. Klebniczki , M. Gorbe , P. Nagy

Dual terahertz (THz) comb spectroscopy is a promising methods for high accuracy, high resolution, and broadband THz spectroscopy because the mode-resolved THz comb spectrum possesses both characteristics of broadband THz radiation and…

Coherent, continuous-wave, and electrically tunable chip-scale terahertz (THz) sources are critical for emerging applications in sensing, imaging, spectroscopy, communication, space and quantum technologies. Here, we demonstrate a robust…

Due to its fast and high resolution characteristics, dual-comb spectroscopy has attracted an increasing amount of interest since its first demonstration. In the terahertz frequency range where abundant absorption lines (finger prints) of…

We introduce a new type of lens that focuses a plane wave into a spherical one, where light comes from all directions. Our method also suggests the design of ideal optical tweezers or, in the reverse direction, photo-detection of nearly all…

Optics · Physics 2025-04-01 Shay Rabani , Kirill Shvalb , Boris Malomed , Tal Carmon

We measure the angular divergence of a quasi-continuous, rf-outcoupled, free-falling atom laser as a function of the outcoupling frequency. The data is compared to a Gaussian-beam model of laser propagation that generalizes the standard…

Condensed Matter · Physics 2009-11-07 Y. Le Coq , J. H. Thywissen , S. A. Rangwala , F. Gerbier , S. Richard , G. Delannoy , P. Bouyer , A. Aspect

In this paper we present weak lensing observations of the fields around 8 z~1 luminous radio sources. These data are searched for the lensing signatures of clusters that are either physically associated with the radio objects, or are…

Astrophysics · Physics 2015-06-24 Richard G. Bower , Ian Smail

We present a technique to estimate the proportion of coherent emission in the light emitted by a practical laser source without spectral filtering. The technique is based on measuring interferometric photon correlations between the output…

Quantum Physics · Physics 2024-01-17 Xi Jie Yeo , Eva Ernst , Alvin Leow , Jaesuk Hwang , Lijiong Shen , Christian Kurtsiefer , Peng Kian Tan

Diffractive X-ray telescopes using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution several orders of magnitude better than available in…

Instrumentation and Methods for Astrophysics · Physics 2010-09-14 Gerald K. Skinner

Tunable lasers, with the ability to continuously adjust their emission wavelengths, have found widespread applications across various fields such as biomedical imaging, coherent ranging, optical communications and spectroscopy. In these…

Optics · Physics 2024-03-22 Baoqi Shi , Yi-Han Luo , Wei Sun , Yue Hu , Jinbao Long , Xue Bai , Anting Wang , Junqiu Liu

Some considerations of long wavelength and broadband radiation sources based on the emission of the coherent radiation by a train of short relativistic electron bunches moving in an open resonator along an arc-like or undulator trajectories…

Classical Physics · Physics 2008-02-03 Yu. Shibata , E. G. Bessonov

The brightness of a light source defines its applicability to nonlinear phenomena in science. Bright low frequency terahertz (< 5THz) radiation confined to a diffraction-limited spot size is a present hurdle due to the broad bandwidth and…

Optics · Physics 2014-07-08 Mostafa Shalaby , Christoph P. Hauri

Spintronic terahertz emitters promise terahertz sources with an unmatched broad frequency bandwidth that are easy to fabricate and operate, and therefore easy to scale at low cost. However, current experiments and proofs of concept rely on…

The spatial coherence of laser sources has limited their application to parallel imaging and projection due to coherent artifacts, such as speckle. In contrast, traditional incoherent light sources, such as thermal sources or light emitting…

Optics · Physics 2017-03-30 B. Redding , A. Cerjan , X. Huang , M. L. Lee , A. D. Stone , M. A. Choma , H. Cao

Frequency-angular distributions for THz emission in the range of 0.1 - 3 THz generated in a single-color laser filament plasma situated both under and without electrostatic field are for the first time experimentally studied. The angular…

Scaling femtosecond terahertz (THz) and ultraviolet (UV) sources to high repetition rates is essential for high-throughput ultrafast spectroscopy and imaging applications. Yet, their efficient generation at high average power remains…

Optics · Physics 2026-01-06 Andrey Ryabov , Kasra Amini

Electromagnetic radiation within the terahertz (THz) frequency range is of great interest for applications in remote sensing and time-domain spectroscopy. The laser-induced plasmas are promising mediums for generating THz radiation. It has…

We propose the use of wavelength-dependent spectroscopic absorption in the evanescent field of ultra-compact whispering gallery mode microspherical lasers as selective gas sensors and estimate few ppm detection sensitivity using a simple…

Instrumentation and Detectors · Physics 2018-07-10 Behsan Behzadi , Ravinder K. Jain , Mani Hossein-Zadeh

We demonstrate a method to double the collection efficiency in Laser Tweezers Raman Spectroscopy (LTRS) by collecting both the forward and back-scattered light in a single-shot multitrack measurement. Our method can collect signals at…

Optics · Physics 2021-06-09 Tobias Dahlberg , Magnus Andersson

Photons, electrons, and their interplay are at the heart of photonic devices and modern instruments for ultrafast science [1-10]. Nowadays, electron beams of the highest intensity and brightness are created by photoemission with short laser…