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226
Magnetic Field Dependence of Ultracold Inelastic Collisions near a Feshbach Resonance
, 2000
"... Inelastic collision rates for ultracold 85 Rb atoms in the F=2, mf=–2 state have been measured as a function of magnetic field. At 250 Gauss (G), the two and threebody loss rates were measured to be K2=1.87±0.95±0.19 x 10 −14 cm 3 /s and K3=4.24 +0.70 −0.29 ±0.85 x 10−25 cm 6 /s respectively. As t ..."
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Inelastic collision rates for ultracold 85 Rb atoms in the F=2, mf=–2 state have been measured as a function of magnetic field. At 250 Gauss (G), the two and threebody loss rates were measured to be K2=1.87±0.95±0.19 x 10 −14 cm 3 /s and K3=4.24 +0.70 −0.29 ±0.85 x 10−25 cm 6 /s respectively. As the magnetic field is decreased from 250 G towards a Feshbach resonance at 155 G, the inelastic rates decrease to a minimum and then increase dramatically, peaking at the Feshbach resonance. Both two and threebody losses are important, and individual contributions have been compared with theory. Typeset using REVTEX 1 Feshbach resonances have recently been observed in a variety of cold atom interactions, including elastic scattering [1], radiative collisions and enhanced inelastic loss [2], photoassociation [3], and the loss of atoms from a BoseEinstein condensate (BEC) [4]. By changing the magnetic field through the resonance, elastic collision rates can be changed by orders
Astrophysical and cosmological tests of quantum theory
 Journal of Physics A: Mathematical and Theoretical
, 2007
"... We outline several proposals for astrophysical and cosmological tests of quantum theory. The tests are motivated by deterministic hiddenvariables theories, and in particular by the view that quantum physics is merely an effective theory of an equilibrium state. The proposed tests involve searching ..."
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We outline several proposals for astrophysical and cosmological tests of quantum theory. The tests are motivated by deterministic hiddenvariables theories, and in particular by the view that quantum physics is merely an effective theory of an equilibrium state. The proposed tests involve searching for nonequilibrium violations of quantum theory in: primordial inflaton fluctuations imprinted on the cosmic microwave background, relic cosmological particles, Hawking radiation, photons with entangled partners inside black holes, neutrino oscillations,
Scaling in Nature: from DNA through Heartbeats to Weather
"... The purpose of this talk is to describe some recent progress in applying scaling concepts to various systems in nature. We review several systems characterized by scaling laws such as DNA sequences, heartbeat rates and weather variations. We discuss the finding that the exponent ff quantifying the s ..."
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The purpose of this talk is to describe some recent progress in applying scaling concepts to various systems in nature. We review several systems characterized by scaling laws such as DNA sequences, heartbeat rates and weather variations. We discuss the finding that the exponent ff quantifying the scaling in DNA is smaller for coding than for noncoding sequences. We also discuss the application of fractal scaling analysis to the dynamics of heartbeat regulation, and report the recent finding that the scaling exponent ff is smaller during sleep periods compared to wake periods. We also discuss the recent findings that suggest a universal scaling exponent characterizing the weather fluctuations. Key words: DNA, heartbeat, weather, time series, scaling, fractals In the last decade it was realized that many systems in nature have no characteristic length or time scale, i.e., they have fractal  or, more generally, scaling  properties [115]. However, the fractal properties in different...
Wol e, Magnetic order and transport in the heavyfermion system CeCu6−xAux, Eur
 Phys. J. B
, 1999
"... Abstract. We report on extensive elastic neutron scattering to determine the wave vector of the magnetic order in CeCu6−xAux single crystals for x> 0.1. For all values of x investigated (0.2, 0.3, 0.5, 1.0) we find longrange incommensurate antiferromagnetic order with an ordering vector Q ≈ (0.625 ..."
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Abstract. We report on extensive elastic neutron scattering to determine the wave vector of the magnetic order in CeCu6−xAux single crystals for x> 0.1. For all values of x investigated (0.2, 0.3, 0.5, 1.0) we find longrange incommensurate antiferromagnetic order with an ordering vector Q ≈ (0.625 0 0.275) for x = 0.2, nearly unchanged for x = 0.3, and Q ≈ (0.59 0 0) for x = 0.5, staying roughly the same
Lowtemperature dephasing in disordered conductors: experimental aspects
, 1999
"... Abstract. What is the lowest temperature to which one can trace the growth of the dephasing time τϕ in lowdimensional conductors? I consider the fundamental limitation, the crossover from weak to strong localization, as well as several experimental reasons for frequently observed saturation of τϕ ( ..."
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Abstract. What is the lowest temperature to which one can trace the growth of the dephasing time τϕ in lowdimensional conductors? I consider the fundamental limitation, the crossover from weak to strong localization, as well as several experimental reasons for frequently observed saturation of τϕ (hotelectron effects, dephasing by external noise). Recent progress in our understanding of the electronphonon interaction in disordered conductors is also briefly discussed.
Quantum Information Processing with Trapped Neutral Atoms
, 2004
"... Quantum information can be processed using large ensembles of ultracold and trapped neutral atoms, building naturally on the techniques developed for highprecision spectroscopy and metrology. This article reviews some of the most important protocols for universal quantum logic with trapped neutrals ..."
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Quantum information can be processed using large ensembles of ultracold and trapped neutral atoms, building naturally on the techniques developed for highprecision spectroscopy and metrology. This article reviews some of the most important protocols for universal quantum logic with trapped neutrals, as well as the history and stateoftheart of experimental work to implement these in the laboratory. Some general observations are made concerning the different strategies for qubit encoding, transport and interaction, including tradeoffs between decoherence rates and the likelihood of twoqubit gate errors. These tradeoffs must be addressed through further refinements of logic protocols and trapping technologies before one can undertake the design of a generalpurpose neutralatom quantum processor.
On the muon capture in 28 Si and extraction of gp
 Proceedings of the 7th International Conference on Mesons and Light Nuclei 98, Pruhonice
, 1998
"... Comparison of the new data for the negative muon capture in 28 Si with the recent shell model calculations using a full 1s0d model space and the USD empirical effective interaction and the onenucleon weak current provides the induced pseudoscalar gP substantially smaller than the value predicted b ..."
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Comparison of the new data for the negative muon capture in 28 Si with the recent shell model calculations using a full 1s0d model space and the USD empirical effective interaction and the onenucleon weak current provides the induced pseudoscalar gP substantially smaller than the value predicted by PCAC and pionpole dominance. We find that adding the effect from the onepion exchange axial charge density and using the same scheme of calculations does not change situation to the value of gP. 1
Pairing in cuprates from high energy electronic states
, 2008
"... The inplane optical conductivity of Bi2Sr2CaCu2O8+δ thin films with small carrier density (underdoped) up to large carrier density (overdoped) is analyzed with unprecedented accuracy. Integrating the conductivity up to increasingly higher energies points to the energy scale involved when the superf ..."
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The inplane optical conductivity of Bi2Sr2CaCu2O8+δ thin films with small carrier density (underdoped) up to large carrier density (overdoped) is analyzed with unprecedented accuracy. Integrating the conductivity up to increasingly higher energies points to the energy scale involved when the superfluid condensate builds up. In the underdoped sample, states extending up to 2 eV contribute to the superfluid. This anomalously large energy scale may be assigned to a change of inplane kinetic energy at the superconducting transition, and is compatible with an electronic pairing mechanism.
ON THE STRUCTURE OF THE SCALAR MESONS f0(975) AND a0(980)
, 1994
"... We investigate the structure of the scalar mesons f0(975) and a0(980) within realistic mesonexchange models of the ππ and πη interactions. Starting from a modified version of the Jülich model for ππ scattering we perform an analysis of the pole structure of the resulting scattering amplitude and fi ..."
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We investigate the structure of the scalar mesons f0(975) and a0(980) within realistic mesonexchange models of the ππ and πη interactions. Starting from a modified version of the Jülich model for ππ scattering we perform an analysis of the pole structure of the resulting scattering amplitude and find, in contrast to existing models, a somewhat large mass for the f0(975) (mf0 = 1015 MeV, Γf0 = 30 MeV). It is shown that our model provides a description of J/ψ → φππ/φKK data comparable in quality with those of alternative models. Furthermore, the formalism developed for the ππ system is consistently extended to the πη interaction leading to a description of the a0(980) as a dynamically generated threshold effect (which is therefore neither a conventional qq state nor a KK bound state). Exploring the corresponding pole 1 position the a0(980) is found to be rather broad (ma0 = 991 MeV, Γa0 = 202 MeV). The experimentally observed smaller width results from the influence of the nearby KK threshold on this pole.
Status of Evidence for Neutrinoless Double Beta Decay
, 2003
"... Abstract. The present experimental status in the search for neutrinoless double beta decay is reviewed, with emphasis on the first indication for neutrinoless double beta decay found in the HEIDELBERGMOSCOW experiment, giving first evidence for lepton number violation and a Majorana nature of the n ..."
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Abstract. The present experimental status in the search for neutrinoless double beta decay is reviewed, with emphasis on the first indication for neutrinoless double beta decay found in the HEIDELBERGMOSCOW experiment, giving first evidence for lepton number violation and a Majorana nature of the neutrinos. Future perspectives of the field are briefly outlined. 1