A5032895604- Cold Atom Physics and Bose-Einstein Condensates
- Quantum, superfluid, helium dynamics
- Atomic and Subatomic Physics Research
- Advanced Chemical Physics Studies
- Quantum optics and atomic interactions
- Advanced Frequency and Time Standards
- Spectroscopy and Laser Applications
- Atomic and Molecular Physics
- Quantum Information and Cryptography
- Strong Light-Matter Interactions
- Laser-Matter Interactions and Applications
- Spectroscopy and Quantum Chemical Studies
- Quantum chaos and dynamical systems
- Quantum Mechanics and Applications
- Laser Design and Applications
- Various Chemistry Research Topics
- Mass Spectrometry Techniques and Applications
- Inorganic Fluorides and Related Compounds
- Nuclear Physics and Applications
- Quantum many-body systems
- Experimental and Theoretical Physics Studies
- Quantum Computing Algorithms and Architecture
- Scientific Measurement and Uncertainty Evaluation
- Laser-induced spectroscopy and plasma
- Mechanical and Optical Resonators
Temple University
2015-2024
Temple College
2020-2023
Philadelphia University
2020-2021
University of Washington
2016
Yale University
2012
National Institute of Standards and Technology
1998-2012
University of Colorado Boulder
2008
Joint Quantum Institute
2008
St Petersburg University
2005
National Institute of Standards
2002-2005
A quantum gas of ultracold polar molecules, with long-range and anisotropic interactions, not only would enable explorations a large class many-body physics phenomena but also could be used for information processing. We report on the creation an dense potassium-rubidium ( 40 K 87 Rb) molecules. Using single step STIRAP (stimulated Raman adiabatic passage) two-frequency laser irradiation, we coherently transfer extremely weakly bound KRb molecules to rovibrational ground state either triplet...
Abstract Ultracold polar molecules combine a rich structure of long-lived internal states with access to controllable long-range anisotropic dipole–dipole interactions. In particular, the rotational confined in optical tweezers or lattices may be used encode interacting qubits for quantum computation pseudo-spins simulating magnetism. As all platforms, engineering robust coherent superpositions is vital. However, optically trapped molecules, coherence time between typically limited by...
We propose a precision measurement of time variations the proton-electron mass ratio using ultracold molecules in an optical lattice. Vibrational energy intervals are sensitive to changes ratio. In contrast measurements that use hyperfine-interval-based atomic clocks, scheme discussed here is model independent and does not require separation different physical constants. The possibility applying zero-differential-Stark-shift lattice technique explored measure vibrational transitions at high accuracy.
We propose new experiments with high sensitivity to a possible variation of the electron-to-proton mass ratio $\ensuremath{\mu}\ensuremath{\equiv}{m}_{e}/{m}_{p}$. consider nearly degenerate pair molecular vibrational levels, each associated different electronic potential. With respect change in $\ensuremath{\mu}$, splitting between such levels can be large both on an absolute scale and relative splitting. demonstrate existence pairs states ${\mathrm{Cs}}_{2}$, where narrow spectral lines...
We have studied interspecies scattering in an ultracold mixture of $^{87}$Rb and $^{133}$Cs atoms, both their lowest-energy spin states. The three-body loss signatures 30 incoming s- p-wave magnetic Feshbach resonances over the range 0 to 667 G been catalogued. Magnetic field modulation spectroscopy was used observe molecular states bound by up 2.5 MHz$\times h$. moment along magneto-association pathway from 197 182 gives results consistent with observed calculated dependence binding energy...
Ultracold 174Yb+ ions and 40Ca atoms are confined in a hybrid trap. The charge exchange chemical reaction rate constant between these two species is measured found to be 4 orders of magnitude larger than recent measurements other heteronuclear systems. structure the CaYb+ molecule determined used calculation that explains fast as consequence strong radiative transfer. A possible explanation offered for apparent contradiction typical theoretical predictions association process this experiments.
In a combined experimental and theoretical effort, we demonstrate novel type of dipolar system made ultracold bosonic molecules with large magnetic dipole moments. Our are formed in weakly bound Feshbach molecular states from sample strongly erbium atoms. We show that the can carry very moments how to create characterize them, change their orientation. Finally, confirm relaxation rates quasi-two dimensional geometry be reduced by using anisotropy dipole-dipole interaction this reduction...
We show that, by loading a Bose-Einstein condensate of two different atomic species into an optical lattice, it is possible to achieve Mott-insulator phase with exactly one atom each per lattice site. A subsequent photoassociation leads the formation heteronuclear molecule large electric dipole moment, at The melting such dipolar Mott insulator creates superfluid, and eventually molecular condensate.
The total energies of atoms and with atomic number Z from 1 to 92 singly charged cations 2 have been calculated an accuracy \ensuremath{\mu}hartree within four variants the Kohn-Sham local-density approximation (LDA). approximations considered are approximation, local-spin-density relativistic scalar-relativistic approximation. for LDA found be in 0.1% agreement a large expansion many-body theory Z\ensuremath{\geqslant}40. A comparison experiment is made ionization spin-orbit splittings;...
Ultracold RbCs molecules in high-lying vibrational levels of the a3Sigma+ ground electronic state are confined an optical trap. Inelastic collision rates these with both Rb and Cs atoms determined for individual levels, across order magnitude binding energies. The long-range dispersion coefficients process calculated used a model that accurately reproduce observed scattering rates.
We report the measurement of anisotropic AC polarizability ultracold polar $^{40}$K$^{87}$Rb molecules in ground and first rotationally excited states. Theoretical analysis agrees well with experimental findings. Although can vary by more than 30%, a "magic" angle between laser polarization quantization axis is found where $|N=0,m_N=0>$ $|N=1,m_N=0>$ states match. At this angle, rotational decoherence due to mismatch trapping potentials eliminated, we observe sharp increase coherence time....
We have produced large samples of stable ultracold (88)Sr(2) molecules in the electronic ground state an optical lattice. The fast, all-optical method molecule creation involves a near-intercombination-line photoassociation pulse followed by spontaneous emission with near-unity Franck-Condon factor. detection uses excitation to weakly bound electronically excited vibrational level corresponding very dimer and yields high-Q molecular vibronic resonance. This is first two steps needed create...
We show that for ultracold magnetic lanthanide atoms chaotic scattering emerges due to a combination of anisotropic interaction potentials and Zeeman coupling under an external field. This is studied in collaborative experimental theoretical effort both dysprosium erbium. present extensive atom-loss measurements their dense Feshbach-resonance spectra, analyze statistical properties, compare predictions from random-matrix-theory-inspired model. Furthermore, coupled-channels simulations the...
Abstract A fundamental question in the study of chemical reactions is how proceed at a collision energy close to absolute zero. This no longer hypothetical: quantum degenerate gases atoms and molecules can now be created temperatures lower than few tens nanokelvin. Here we consider benchmark ultracold reaction between, most-celebrated molecule, KRb K. We map out an accurate ab initio ground-state potential surface K 2 Rb complex full dimensionality report numerically-exact quantum-mechanical...
Superpositions of rotational states in polar molecules induce strong, long-range dipolar interactions. Here we extend the coherence by nearly one order magnitude to 8.7(6) ms a dilute gas $^{23}$Na$^{40}$K an optical trap. We demonstrate spin-decoupled magic trapping, which cancels first-order and reduces second-order differential light shifts. The latter is achieved with dc electric field that decouples nuclear spin, rotation trapping field. observe density-dependent times, can be explained...
Progress in ultracold experiments with polar molecules requires a clear understanding of their interactions and reactivity at ultra-low collisional energies. Two important theoretical steps this process are the characterization interaction potentials between modeling reactive scattering mechanism. Here, we report on {\it abinitio} calculation isotropic anisotropic van der Waals for KRb RbCs colliding each other or atoms. Based these two short-range parameters then develop single-channel...
We explore the anisotropic nature of Feshbach resonances in collision between ultracold highly magnetic submerged-shell dysprosium atoms their energetically lowest sublevel, which can only occur due to couplings rotating bound states. This is contrast well-studied alkali-metal atom collisions, where broadest (strongest) are hyperfine induced and rotationless Our first-principle coupled-channel calculation collisions these spin-polarized bosonic reveals a strong interplay anisotropies...
We report on the observation of magnetic Feshbach resonances in a Fermi-Fermi mixture ultracold atoms with extreme mass imbalance and their unique p-wave dominated three-body recombination processes. Our system consists open-shell alkali-metal 6Li closed-shell 173Yb atoms, both spin polarized held at various temperatures between 1 20 μK. confirm that this are solely result weak separation-dependent hyperfine coupling electronic nuclear 173Yb. analysis also shows rates controlled by identical...
We use narrow-band laser excitation of Yb to substantially enhance the brightness a cold beam YbOH, polyatomic molecule with high sensitivity physics beyond Standard Model (BSM). By exciting atomic metastable $^3$P$_1$ state in cryogenic environment, we significantly increase chemical reaction cross-section for collisions reactants. characterize dependence enhancement on properties light, and study final distribution YbOH products. The resulting bright, can be used statistical searches new...