Pairing in spin polarized two-species fermionic mixtures with mass asymmetry

We discuss on the pairing mechanism of fermions with mismatch in their fermi momenta due to a mass asymmetry. Using a variational ansatz for the ground state we also discuss the BCS -BEC crossover of this system. It is shown that the breached pairing solution with a single fermi surface is stable in the BEC regime. We also include the temperatures effect on the fermion pairing within an approximation that is valid for temperatures much below the critical temperature.Comment: 8 pages and 6 figures, few typos corrected, version to appear in EPJ

Repulsion and attraction in high Tc superconductors

The influence of repulsion and attraction in high-Tc superconductors to the gap functions is studied. A systematic method is proposed to compute the gap functions using the irreducible representations of the point group. It is found that a pure s-wave superconductivity exists only at very low temperatures, and attractive potentials on the near shells significantly expand the gap functions and increase significantly the critical temperature of superconductivity. A strong on-site repulsion drives the $A_{1g}$ gap into a $B_{1g}$ gap. It is expected that superconductivity with the $A_{1g}$ symmetry reaches a high critical temperature due to the cooperation of the on-site and the next-nearest neighbor attractions.Comment: 4 pages, 5figure

p-wave phase shift and scattering length of 6^6Li

We have calculated the p-wave phase shifts and scattering length of $^6$Li. For this we solve the $p$ partial wave Schr\"odinger equation and analyze the validity of adopting the semiclassical solution to evaluate the constant factors in the solution. Unlike in the $s$ wave case, the semiclassical solution does not provide unique value of the constants. We suggest an approximate analytic solution, which provides reliable results in special cases. Further more, we also use the variable phase method to evaluate the phase shifts. The p-wave scattering lengths of $^{132}$Cs and $^{134}$Cs are calculated to validate the schemes followed. Based on our calculations, the value of the $p$ wave scattering length of $^6$Li is $-45a_o$.Comment: 10 figure

Superfluid phase transition and strong-coupling effects in an ultracold Fermi gas with mass imbalance

We investigate the superfluid phase transition and effects of mass imbalance in the BCS (Bardeen-Cooper-Schrieffer)-BEC (Bose-Einstein condensation) crossover regime of an cold Fermi gas. We point out that the Gaussian fluctuation theory developed by Nozi\`eres and Schmitt-Rink and the $T$-matrix theory, that are now widely used to study strong-coupling physics of cold Fermi gases, give unphysical results in the presence of mass imbalance. To overcome this problem, we extend the $T$-matrix theory to include higher-order pairing fluctuations. Using this, we examine how the mass imbalance affects the superfluid phase transition. Since the mass imbalance is an important key in various Fermi superfluids, such as $^{40}$K-$^6$Li Fermi gas mixture, exciton condensate, and color superconductivity in a dense quark matter, our results would be useful for the study of these recently developing superfluid systems.Comment: 7 pages, 4 figures, Proceedings of QFS-201

Fermionic superfluidity: From high Tc superconductors to ultracold Fermi gases

We present a pairing fluctuation theory which self-consistently incorporates finite momentum pair excitations in the context of BCS--Bose-Einstein condensation (BEC) crossover, and we apply this theory to high $T_c$ superconductors and ultracold Fermi gases. There are strong similarities between Fermi gases in the unitary regime and high Tc superconductors. Here we address key issues of common interest, especially the pseudogap. In the Fermi gases we summarize recent experiments including various phase diagrams (with and without population imbalance), as well as evidence for a pseudogap in thermodynamic and other experiments.Comment: Expanded version, invited talk at the 5th International Conference on Complex Matter -- Stripes 2006, 6 pages, 6 figure

Pneumocysterol [ (24Z) - ethylidenelanost - 8 - en -3 rare sterol detected in opportunistic pathogen Pneumocyctis carinii hominis : Structural identity and chemical synthesis

Edna S. Kaneshiro, Zunika Amit, Mardie M. Swonger, George P. Kreishman, Elwood E. Brooks, Mara Kreishman, Koka Jayasimhulu, Hang Sun, Stephen A. Kizito, David H. Beach, Edward J. Parish

Thermodynamics of Dipolar Chain Systems

The thermodynamics of a quantum system of layers containing perpendicularly oriented dipolar molecules is studied within an oscillator approximation for both bosonic and fermionic species. The system is assumed to be built from chains with one molecule in each layer. We consider the effects of the intralayer repulsion and quantum statistical requirements in systems with more than one chain. Specifically, we consider the case of two chains and solve the problem analytically within the harmonic Hamiltonian approach which is accurate for large dipole moments. The case of three chains is calculated numerically. Our findings indicate that thermodynamic observables, such as the heat capacity, can be used to probe the signatures of the intralayer interaction between chains. This should be relevant for near future experiments on polar molecules with strong dipole moments.Comment: 15 pages, 5 figures, final versio

Thermodynamics of Trapped Imbalanced Fermi Gases at Unitarity

We present a theory for the low-temperature properties of a resonantly interacting Fermi mixture in a trap, that goes beyond the local-density approximation. The theory corresponds essentially to a Landau-Ginzburg-like approach that includes self-energy effects to account for the strong interactions at unitarity. We show diagrammatically how these self-energy effects arise from fluctuations in the superfluid order parameter. Gradient terms of the order parameter are included to account for inhomogeneities. This approach incorporates the state-of-the-art knowledge of the homogeneous mixture with a population imbalance exactly and gives good agreement with the experimental density profiles of Shin et al. [Nature 451, 689 (2008)]. This allows us to calculate the universal surface tension of the interface between the equal-density superfluid and the partially polarized normal state of the mixture. We also discuss the possibility of a metastable state to explain the deformation of the superfluid core that is seen in the experiment of Partridge et al. [Science 311, 503 (2006)].Comment: 26 pages, 7 figures, contribution to Lecture Notes in Physics "BCS-BEC crossover and the Unitary Fermi Gas" edited by W. Zwerge

Health Disparities and the Digital Divide: The Relationship between Communication Inequalities and Quality of Life among Women in a Nationwide Prospective Cohort Study in the United States

Background: Communication inequalities can affect health-seeking behaviors yet the relationship between Internet use and overall health is inconclusive. Communication-related inequalities vary by race/ethnicity and SES but existing research primarily includes middle-class Whites. We therefore examined the relationship between communication-related inequalities—measured by daily Internet use—and health-related quality of life (QOL) using a nationwide prospective cohort study in the United States that consists of primarily low income, minority women. Methods: We examined Internet use and QOL among participants in the Women’s Interagency HIV Study. Data collection occurred from October 2014-September 2015 in Chicago, New York, Washington DC, San Francisco, Atlanta, Chapel Hill, Birmingham/Jackson and Miami. We used multi-variable analyses to examine the relationship between daily Internet use and QOL. Results: The sample of 1,915 women was 73% African American and 15% Hispanic; 53% reported an annual income of ≤$12,000. Women with daily Internet use reported a higher QOL at six months, as did women with at least a high school diploma, income >$12,000, and non-White race; older women and those with reported drug use, depressive symptoms and loneliness had lower QOL. Conclusions: Overcoming communication inequalities may be one pathway through which to improve overall QOL and address public health priorities. Reducing communication-related inequalities—e.g, by providing reliable Internet access—and thus improving access to health promoting information, may lead to improved health outcomes

Multisite Study of Women Living With HIV's Perceived Barriers to, and Interest in, Long-Acting Injectable Antiretroviral Therapy

BACKGROUND: Adherence to antiretroviral therapy (ART) is imperative for viral suppression and reducing HIV transmission, but many people living with HIV report difficultly sustaining long-term adherence. Long-acting injectable (LAI) ART has the potential to transform HIV treatment and prevention. However, little LAI ART-related behavioral research has occurred among women, particularly outside of clinical trials. SETTING: Six Women's Interagency HIV Study sites: New York, Chicago, Washington DC, Atlanta, Chapel Hill, and San Francisco. METHODS: We conducted 59 in-depth interviews with women living with HIV across 6 Women's Interagency HIV Study sites (10 per site; 9 at Washington DC). We interviewed women who were not included in LAI ART clinical trials but who receive care at university settings that will administer LAI ART once it is approved. Interviews were recorded, transcribed, and analyzed using thematic content analysis. RESULTS: Most women enthusiastically endorsed monthly LAI ART and would prefer it over pills. The following 3 reasons emerged for this preference: (1) convenience and confidentiality, (2) avoiding daily reminders about living with HIV, and (3) believing that shots are more effective than pills. Challenges remain, however, specifically around (1) medical mistrust, (2) concerns about safety and effectiveness, (3) pill burden for HIV and other conditions, and (4) barriers to additional medical visits. CONCLUSIONS: Most women preferred LAI ART over daily pills given its benefits, including convenience, privacy, and perceived effectiveness. Future research should incorporate more women into LAI ART trials to better understand and align development with user concerns and preferences to enhance uptake