281 research outputs found

    Observation of blue-shifted ultralong-range Cs2_{2} Rydberg molecules

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    We observe ultralong-range blue-shifted Cs2_{2} molecular states near ns1/2ns_{1/2} Rydberg states in an optical dipole trap, where 31n3431\leq n\leq34. The accidental near degeneracy of (n4)l(n-4)l and nsns Rydberg states for l>2l>2 in Cs, due to the small fractional nsns quantum defect, leads to non-adiabatic coupling among these states, producing potential wells above the nsns thresholds. Two important consequences of admixing high angular momentum states with nsns states are the formation of large permanent dipole moments, 15100\sim 15-100\,Debye, and accessibility of these states via two-photon association. The observed states are in excellent agreement with theory. Both projections of the total angular momentum on the internuclear axis are visible in the experiment

    Tuning p-wave interactions in an ultracold Fermi gas of atoms

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    We have measured a p-wave Feshbach resonance in a single-component, ultracold Fermi gas of potassium atoms. We have used this resonance to enhance the normally suppressed p-wave collision cross-section to values larger than the background s-wave cross-section between potassium atoms in different spin-states. In addition to the modification of two-body elastic processes, the resonance dramatically enhances three-body inelastic collisional loss.Comment: 4 pages, 5 figure

    Liver function and anemia pathogenesis in Iranian traditional medicine

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    Background: Nutritional deficiency, bleeding, and inflammation are three main causes of anemia. On the other hand, erythropoietin (EPO) production, iron availability, and a healthy bone marrow are essential for erythropoiesis. Recently, recombinant human erythropoietin (rhEPO) has been used to treat the patients already taking iron supplements. In Iranian traditional medicine literature, much has been written about anemia and its treatment. Objectives: This study aimed to review Iranian traditional medicine theories in the treatment of anemia. Materials and Methods: In the present study, authors have attempted to find the etiology and pathogenesis of anemia in Iranian traditional Medicine Literature and the views of ancient physicians in this field. Results: Our findings proved that Iranian traditional medicine defined anemia as blood humor production dysfunction, which is caused by several reasons mainly hepatic dysfunction. Thus, liver is supposed to be the most important organ in this regard. This will make considering hepatoprotective medicines in anemia even in patients with non-hepatic problems. Conclusions: The article presents the relation between anemia and liver dysfunction viewed by Iranian traditional medicine as an important finding in designing a treatment plan. Despite the new findings on the evaluation of liver function (i.e. laboratory tests), it seems that further studies for earlier evaluation of liver function in anemia are highly required. © 2015 Iranian Red Crescent Medical Journal

    Depolarisation cooling of an atomic cloud

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    We propose a cooling scheme based on depolarisation of a polarised cloud of trapped atoms. Similar to adiabatic demagnetisation, we suggest to use the coupling between the internal spin reservoir of the cloud and the external kinetic reservoir via dipolar relaxation to reduce the temperature of the cloud. By optical pumping one can cool the spin reservoir and force the cooling process. In case of a trapped gas of dipolar chromium atoms, we show that this cooling technique can be performed continuously and used to approach the critical phase space density for BECComment: 8 pages, 5 figure

    Ultralong-Range Rydberg Molecules in a Divalent-Atomic System

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    We report the creation of ultralong-range Sr2_2 molecules comprising one ground-state 5s25s^2 1S0^1S_0 atom and one atom in a 5sns5sns 3S1^3S_1 Rydberg state for nn ranging from 29 to 36. Molecules are created in a trapped ultracold atomic gas using two-photon excitation near resonant with the 5s5p5s5p 3P1^3P_1 intermediate state, and their formation is detected through ground-state atom loss from the trap. The observed molecular binding energies are fit with the aid of first-order perturbation theory that utilizes a Fermi pseudopotential with effective ss-wave and pp-wave scattering lengths to describe the interaction between an excited Rydberg electron and a ground-state Sr atom.Comment: 5 pages, 2 figure

    Electric-field noise from carbon-adatom diffusion on a Au(110) surface: first-principles calculations and experiments

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    The decoherence of trapped-ion quantum gates due to heating of their motional modes is a fundamental science and engineering problem. This heating is attributed to electric-field noise arising from the trap-electrode surfaces. In this work, we investigate the source of this noise by focusing on the diffusion of carbon-containing adsorbates on the surface of Au(110). We show by density functional theory, based on detailed scanning probe microscopy, how the carbon adatom diffusion on the gold surface changes the energy landscape, and how the adatom dipole moment varies with the diffusive motion. A simple model for the diffusion noise, which varies quadratically with the variation of the dipole moment, qualitatively reproduces the measured noise spectrum, and the estimate of the noise spectral density is in accord with measured values.Comment: 8 pages, 6 figure
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