A5031177851- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Magnetic properties of thin films
- Scientific Measurement and Uncertainty Evaluation
- Quantum Mechanics and Applications
- Magneto-Optical Properties and Applications
- Magnetic Properties and Applications
- Retinal Development and Disorders
- Geophysics and Sensor Technology
- Metallic Glasses and Amorphous Alloys
- Theoretical and Computational Physics
- Radioactive Decay and Measurement Techniques
- Cosmology and Gravitation Theories
- Metallurgical Processes and Thermodynamics
- Dark Matter and Cosmic Phenomena
- Retinal Diseases and Treatments
- Retinal Imaging and Analysis
- Visual perception and processing mechanisms
- Quantum Information and Cryptography
- Optical Coherence Tomography Applications
- Glaucoma and retinal disorders
- Quantum Electrodynamics and Casimir Effect
- Fluid Dynamics and Mixing
- Retinal and Macular Surgery
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2020-2024
Helmholtz-Zentrum Dresden-Rossendorf
2024
Leibniz University Hannover
2014-2023
RWTH Aachen University
2019-2023
Planetary Science Institute
2023
Jet Propulsion Laboratory
2021
Technische Universität Braunschweig
2013-2017
Johannes Gutenberg University Mainz
2016-2017
University of Freiburg
2016-2017
Chemnitz University of Technology
2010-2015
We simultaneously measure the gravitationally induced phase shift in two Raman-type matter-wave interferometers operated with laser-cooled ensembles of Rb87 and K39 atoms. Our measurement yields an Eötvös ratio ηRb,K=(0.3±5.4)×10−7. briefly estimate possible bias effects present strategies for future improvements.Received 1 April 2014DOI:https://doi.org/10.1103/PhysRevLett.112.203002© 2014 American Physical Society
The theory of general relativity describes macroscopic phenomena driven by the influence gravity while quantum mechanics brilliantly accounts for microscopic effects.Despite their tremendous individual success, a complete unification fundamental interactions is missing and remains one most challenging important quests in modern theoretical physics.The STE-QUEST satellite mission, proposed as medium-size mission within Cosmic Vision program European Space Agency (ESA), aims testing with high...
To compare ultrahigh-resolution optical coherence tomography (OCT) cross-sectional images of the pig retina with histology, to evaluate potential OCT for enhanced visualization intra- and subretinal structures.Ultrahigh-resolution were acquired 1.4- micro m axial x 3- transverse resolution from in vitro posterior eyecup preparations domestic pig. Frozen sections obtained precise alignment tomograms, by using major blood vessels as orientation markers counterstained cresyl violet or unstained...
We demonstrate a quantum gravimeter by combining the advantages of an atom chip for generation, delta-kick collimation, and coherent manipulation freely falling Bose-Einstein condensates (BECs) with innovative launch mechanism based on Bloch oscillations double Bragg diffraction. Our high-contrast BEC interferometer realizes tens milliseconds free fall in volume as little one centimeter cube paves way measurements sub-μGal accuracies miniaturized, robust devices.Received 13 May...
All-optical switching (AOS) in ferrimagnetic Fe100-xTbx alloys is presented. AOS witnessed below, above, and samples without a magnetic compensation point. It found that associated with laser heating up to the Curie temperature intimately linked low remanent sample magnetization. Above threshold magnetization of 220 emu/cc helicity dependent replaced by pure thermal demagnetization. As service our authors readers, this journal provides supporting information supplied authors. Such materials...
Inertial sensors based on cold atoms have great potential for navigation, geodesy, or fundamental physics. Similar to the Sagnac effect, their sensitivity increases with space-time area enclosed by interferometer. Here, we introduce twin-lattice atom interferometry exploiting Bose-Einstein condensates. Our method provides symmetric momentum transfer and large areas in palm-sized sensor heads a performance similar present meter-scale devices.
We study a space-based gravity gradiometer based on cold atom interferometry and its potential for the Earth's gravitational field mapping. The instrument architecture has been proposed in [Carraz et al., Microgravity Science Technology 26, 139 (2014)] enables high-sensitivity measurements of gradients by using interferometers differential accelerometer configuration. present design including subsystems analyze mission scenario, which we derive expected performances, requirements sensor key...
Deployment of ultracold atom interferometers (AI) into space will capitalize on quantum advantages and the extended freefall persistent microgravity to provide high-precision measurement capabilities for gravitational, Earth, planetary sciences, enable searches subtle forces signifying physics beyond General Relativity Standard Model. NASA's Cold Atom Lab (CAL) operates onboard International Space Station as a multi-user facility fundamental studies atoms mature space-based technologies. We...
In this article the ability of ultrahigh resolution ophthalmic optical coherence tomography (OCT) to image small choroidal blood vessels below highly reflective and absorbing retinal pigment epithelium is demonstrated for first time. A new light source (lambdac= 1050 nm, Deltalambda = 165 Pout= 10 mW), based on a photonic crystal fiber pumped by compact, self-starting Ti:Al2O3 laser has therefore been developed. Ex-vivo OCT images freshly excised pig retinas acquired with demonstrate...
Abstract This study addresses the correlation of retinal topography with factors such as visual environment, life style, and behavior for a major mammalian group, artiodactyls. To provide broader basis semiquantitative comparison, short‐wavelength‐sensitive (S)‐ middle‐to‐long‐wavelength‐sensitive (M)‐opsin cone receptor populations from 25 species five artiodactyl families African elephant were labeled sampled. The resulting topographic maps analyzed respect to position extension...
Compared to light interferometers, the flux in cold-atom interferometers is low and associated shot noise large. Sensitivities beyond these limitations require preparation of entangled atoms different momentum modes. Here, we demonstrate a source that compatible with state-of-the-art interferometers. Entanglement transferred from spin degree freedom Bose-Einstein condensate well-separated modes, witnessed by squeezing parameter -3.1(8) dB. Entanglement-enhanced atom promise unprecedented...
Microgravity eases several constraints limiting experiments with ultracold and condensed atoms on ground. It enables extended times of flight without suspension eliminates the gravitational sag for trapped atoms. These advantages motivated numerous initiatives to adapt operate experimental setups microgravity platforms. We describe design payload, motivations choices, capabilities Bose-Einstein Condensate Cold Atom Laboratory (BECCAL), a NASA-DLR collaboration. BECCAL builds heritage...
Recent developments in quantum technology have resulted a new generation of sensors for measuring inertial quantities, such as acceleration and rotation. These can exhibit unprecedented sensitivity accuracy when operated space, where the free-fall interrogation time be extended at will environment noise is minimal. European laboratories played leading role this field by developing concepts tools to operate these relevant environment, parabolic flights, towers, or sounding rockets. With...
We report on the realization of a compact atomic Mach–Zehnder-type Sagnac interferometer 13.7 cm length, which covers an area 19 mm2 previously reported only for large thermal beam interferometers. According to Sagnac's formula, holds both light and atoms, sensitivity rotation rates increases linearly with enclosed by interferometer. The use cold atoms instead enables miniaturization interferometers without sacrificing areas. In comparison beams, slow offer better matching initial velocity...
Low remanent magnetization as key prerequisite for the ability of helicity dependent all-optical magnetic switching (AOS) is demonstrated an artificial zero moment magnet. A heterostructure consisting two amorphous ferrimagnetic Tb36Fe64 and Tb19Fe81 alloy layers designed to yield a net at room temperature by means antiparallel interfacial exchange coupling dominant moments. The canceling layer magnetizations provide vanishing demagnetization fields AOS. Contrary this, no observed single...
In a quantum version of the twin paradox, atom interferometers generate one clock, aging at different rates simultaneously.