A5072414663- Cold Atom Physics and Bose-Einstein Condensates
- Advanced Frequency and Time Standards
- Quantum Mechanics and Applications
- Atomic and Subatomic Physics Research
- Cosmology and Gravitation Theories
- Black Holes and Theoretical Physics
- Quantum Electrodynamics and Casimir Effect
- Quantum Information and Cryptography
- Advanced Thermodynamics and Statistical Mechanics
- Spectroscopy and Quantum Chemical Studies
- Quantum optics and atomic interactions
- Solar and Space Plasma Dynamics
- Radioactive Decay and Measurement Techniques
- Noncommutative and Quantum Gravity Theories
- Geophysics and Sensor Technology
- Mechanical and Optical Resonators
- Galaxies: Formation, Evolution, Phenomena
- Pulsars and Gravitational Waves Research
- stochastic dynamics and bifurcation
- Physics of Superconductivity and Magnetism
- Strong Light-Matter Interactions
- Advanced Differential Geometry Research
- Experimental and Theoretical Physics Studies
- Space Science and Extraterrestrial Life
- Geophysics and Gravity Measurements
Deutsches Zentrum für Luft- und Raumfahrt e. V. (DLR)
2020-2024
Quantum Technologies (Sweden)
2023-2024
Center for Integrated Quantum Science and Technology
2013-2021
Jet Propulsion Laboratory
2021
Universität Ulm
2012-2020
University of Maryland, College Park
2003-2013
Max Planck Institute for Gravitational Physics
2010-2013
Joint Quantum Institute
2013
Max Planck Society
2012
Universitat de Barcelona
1999-2008
Atom interferometers covering macroscopic domains of space-time are a spectacular manifestation the wave nature matter. Because their unique coherence properties, Bose-Einstein condensates ideal sources for an atom interferometer in extended free fall. In this Letter we report on realization asymmetric Mach-Zehnder operated with condensate microgravity. The resulting interference pattern is similar to one far field double slit and shows linear scaling time packets expand. We employ...
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...
Atom interferometry tests of universality free fall based on the differential measurement two different atomic species provide a useful complement to those macroscopic masses. However, when striving for highest possible sensitivities, gravity gradients pose serious challenge. Indeed, relative initial position and velocity need be controlled with extremely high accuracy, which can rather demanding in practice whose verification may require long integration times. Furthermore, highly sensitive...
Do the laws of quantum physics still hold for macroscopic objects - this is at heart Schrödinger's cat paradox or do gravitation yet unknown effects set a limit massive particles? What fundamental relation between and gravity? Ground-based experiments addressing these questions may soon face limitations due to limited free-fall times quality vacuum microgravity. The proposed mission Macroscopic Quantum Resonators (MAQRO) overcome allow such questions. MAQRO harnesses recent developments in...
The creation of delocalized coherent superpositions quantum systems experiencing different relativistic effects is an important milestone in future research at the interface gravity and mechanics. This could be achieved by generating a superposition clocks that follow paths with gravitational time dilation investigating consequences on interference signal when they are eventually recombined. Light-pulse atom interferometry elements employed optical atomic promising candidate for purpose, but...
We propose a terrestrial detector for gravitational waves with frequencies between 0.3 and 5 Hz based on atom interferometry. As key elements, we discuss two symmetric matter-wave interferometers, the first one single loop second featuring folded triple-loop geometry. The latter eliminates need atomic ensembles at femtokelvin energies imposed by Sagnac effect in other interferometric detectors. geometry also combines several advantages of current vertical horizontal matter wave antennas...
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...
The use of retro-reflection in light-pulse atom interferometry under microgravity conditions naturally leads to a double-diffraction scheme. two pairs counterpropagating beams induce simultaneously transitions with opposite momentum transfer that, when acting on atoms initially at rest, give rise symmetric interferometer configurations where the total is automatically doubled and number noise sources systematic effects cancel out. Here we extend earlier implementations for Raman case Bragg...
We employ light-induced double Bragg diffraction of delta-kick collimated Bose-Einstein condensates to create three symmetric Mach-Zehnder interferometers. They rely on (i) first-order, (ii) two successive and (iii) second-order processes which demonstrate the scalability corresponding momentum transfer. With respect devices based conventional scattering, these interferometers scale factor feature a better suppression noise systematic uncertainties intrinsic process. Moreover, we utilize as...
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...
In this work a two-particle irreducible (2PI) closed-time-path (CTP) effective action is used to describe the nonequilibrium dynamics of Bose-Einstein condensate selectively loaded into every third site one-dimensional optical lattice. The motivation recent experimental realization system. Patterned loading methods may be useful for quantum computing with trapped atoms. This system also serves illustrate many basic issues in quantum-field theory pertaining correlations and fluctuations which...
The Riemann correlator with appropriately raised indices characterizes in a gauge-invariant way the quantum metric fluctuations around de Sitter spacetime including loop corrections from matter fields. Specializing to conformal fields and employing method that selects Sitter-invariant vacuum Poincaré patch, we obtain exact result for through order H4/mp4. is expressed manifestly form terms of maximally symmetric bitensors. Its behavior both short long distances (sub- superhorizon scales)...
In a quantum version of the twin paradox, atom interferometers generate one clock, aging at different rates simultaneously.
We propose a criterion for the validity of semiclassical gravity (SCG) which is based on stability solutions SCG with respect to quantum metric fluctuations. pay special attention two-point correlation functions perturbations, contain both intrinsic and induced These fluctuations can be described by Einstein-Langevin equation obtained in framework stochastic gravity. Specifically, yields perturbations agree, leading order large N limit, theory interacting matter fields. The homogeneous are...
The two-point function for tensor metric perturbations around de Sitter spacetime including one-loop corrections from massless conformally coupled scalar fields is calculated exactly. We work in the Poincaré patch (with spatially flat sections) and employ dimensional regularization renormalization process. Unlike previous studies we obtain result arbitrary time separations rather than just equal times. Moreover, contrast to existing results perturbations, ours manifestly invariant with...
We consider the linearized semiclassical Einstein equations for small deviations around de Sitter spacetime including vacuum polarization effects of conformal fields. Employing method order reduction, we find exact solutions general metric perturbations (of scalar, vector and tensor type). Our (nonperturbative) show clearly that in this case is stable with respect to a late-time attractor. Furthermore, they also reveal breakdown perturbative sufficiently long evolution inside horizon....
Gravitational Waves (GWs) were observed for the first time in 2015, one century after Einstein predicted their existence. There is now growing interest to extend detection bandwidth low frequency. The scientific potential of multi-frequency GW astronomy enormous as it would enable obtain a more complete picture cosmic events and mechanisms. This unique entirely new opportunity future astronomy, success which depends upon decisions being made on existing infrastructures. prospect combining...
We provide a comprehensive study of atomic Raman and Bragg diffraction when coupling to pair counterpropagating light gratings (double diffraction) or single one (single discuss the transition from case other in retroreflective geometry as Doppler detuning changes. In contrast diffraction, double loses its advantage high efficiency for short pulses has be performed Bragg-type regime. Moreover, structure leads further limitations broad momentum distributions on mirror pulses, making use...