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Related papers: Phase-contrast imaging of a dense atomic cloud

200 papers

We demonstrate a scheme for direct absorption imaging of an ultracold ground-state polar molecular gas near quantum degeneracy. A challenge in imaging molecules is the lack of closed optical cycling transitions. Our technique relies on…

Quantum Gases · Physics 2015-05-18 D. Wang , B. Neyenhuis , M. H. G. de Miranda , K. -K. Ni , S. Ospelkaus , D. S. Jin , J. Ye

Stars form in the dense interiors of molecular clouds. The dynamics and physical properties of the atomic interstellar medium (ISM) set the conditions under which molecular clouds and eventually stars will form. It is, therefore, critical…

We demonstrate a compact, spectrally-selective, and tunable delay line for single photons emitted by quantum dots. This is achieved by fine-tuning the wavelength of the optical transitions of such "artificial atoms" into a spectral window…

Mesoscale and Nanoscale Physics · Physics 2015-12-30 Johannes S. Wildmann , Rinaldo Trotta , Javier Martín-Sánchez , Eugenio Zallo , Oliver G. Schmidt , Armando Rastelli

Recent theoretical investigations have indicated that rapid optical cycling should be feasible in complex polyatomic molecules with diverse constituents, geometries and symmetries. However, as a composite molecular mass grows, so does the…

Atomic Physics · Physics 2020-12-18 Konrad Wenz , Ivan Kozyryev , Rees L. McNally , Leland Aldridge , Tanya Zelevinsky

To manipulate cold atoms in spatially constrained quantum engineering platforms, we developed a lensless optical system with a $\sim$1 $\mu$m resolution and a transverse size of only 225 $\mu$m. We use a multimode optical fiber with a high…

Atomic Physics · Physics 2020-03-24 Nicolas Vitrant , Kilian Müller , Sébastien Garcia , Alexei Ourjoumtsev

Molecular hydrogen clouds are a key component of the interstellar medium because they are the birthplaces for stars. They are embedded in atomic gas that pervades the interstellar space. However, the details of how molecular clouds assemble…

We analyze the collisional excitation of the 158 micron (1900.5 GHz) fine structure transition of ionized carbon (C+) in terms of line intensities produced by simple cloud models. The single C+ fine structure transition is a very important…

Astrophysics of Galaxies · Physics 2015-06-11 Paul F. Goldsmith , William D. Langer , Jorge L. Pineda , T. Velusamy

The effect of the dipole-dipole interaction on the far-off-resonance optical dipole trapping scheme is calculated by a mean-field approach. The trapping laser field polarizes the atoms and the accompanying dipole-dipole energy shift deepens…

Atomic Physics · Physics 2009-11-13 D. Nagy , P. Domokos

Sub-micrometer scale light patterns play a pivotal role in various fields, including biology, biophysics, and AMO physics. High-resolution, in situ observation of light profiles is essential for their design and application. However,…

We use a deep neural network to detect and place region-of-interest boxes around ultracold atom clouds in absorption and fluorescence images---with the ability to identify and bound multiple clouds within a single image. The neural network…

Quantum Gases · Physics 2021-08-03 Lucas R. Hofer , Milan Krstajić , Péter Juhász , Anna L. Marchant , Robert P. Smith

We introduce a scheme for deep laser cooling of molecules based on robust dark states at zero velocity. By simulating this scheme, we show it to be a widely applicable method that can reach the recoil limit or below. We demonstrate and…

Atomic Physics · Physics 2019-07-24 L. Caldwell , J. A. Devlin , H. J. Williams , N. J. Fitch , E. A. Hinds , B. E. Sauer , M. R. Tarbutt

While liquid crystals (LCs) have been extensively studied, obtaining a comprehensive nanoscale picture of their molecular organization remains challenging, as conventional techniques face an intrinsic trade-off between spatial and chemical…

We present PPMAP, a Bayesian procedure that uses images of dust continuum emission at multiple wavelengths to produce resolution-enhanced image cubes of differential column-density as a function of dust temperature and position. PPMAP is…

Instrumentation and Methods for Astrophysics · Physics 2015-11-04 K. A. Marsh , A. P. Whitworth , O. Lomax

We implement a simple method for fast and precise delivery of ultracold atoms to a microscopic device, i.e. a Fabry-Perot microcavity. By moving a single beam optical dipole trap in a direction perpendicular to the beam axis with an…

We show how to construct asymmetric optical barriers for atoms. These barriers can be used to compress phase space of a sample by creating a confined region in space where atoms can accumulate with heating at the single photon recoil level.…

Atomic Physics · Physics 2007-05-23 M. G. Raizen , A. M. Dudarev , Qian Niu , N. J. Fisch

We present new observations of [CII] fine structure line emission from an isolated molecular cloud using the upGREAT instrument onboard SOFIA. These data are analyzed together with archival CO=1-0 and HI 21 cm emission spectra to…

Astrophysics of Galaxies · Physics 2022-12-21 Mark Heyer , Paul F. Goldsmith , Robert Simon , Rebeca Aladro , Oliver Ricken

Coded Aperture Imaging (CAI) has been proposed as an alternative collimation technique in nuclear imaging. To maximize spatial resolution small pinholes in the coded aperture mask are required. However, a high-resolution detector is needed…

Medical Physics · Physics 2023-06-16 Tobias Meißner , Werner Nahm , Jürgen Hesser , Nikolas Löw

We propose a novel approach to the important fundamental problem of detecting weak optical fields at the few photon level. The ability to detect with high efficiency (>99%), and to distinguish the number of photons in a given time interval…

Quantum Physics · Physics 2009-11-07 Daniel James , Paul Kwiat

Image Phase Alignment Super-Sampling (ImPASS) is a computational imaging algorithm for converting a sequence of displaced low-resolution images into a single high-resolution image. The method consists of a unique combination of Phase…

Optics · Physics 2025-09-01 James N. Caron

For passive satellite imagers, current retrievals of cloud optical thickness and effective particle size fail for convective clouds with 3D morphology. Indeed, being based on 1D radiative transfer (RT) theory, they work well only for…

Geophysics · Physics 2021-07-13 Linda Forster , Anthony B. Davis , David J. Diner , Bernhard Mayer