Pair-Breaking in Rotating Fermi Gases

We study the pair-breaking effect of rotation on a cold Fermi gas in the BCS-BEC crossover region. In the framework of BCS theory, which is supposed to be qualitatively correct at zero temperature, we find that in a trap rotating around a symmetry axis, three regions have to be distinguished: (A) a region near the rotational axis where the superfluid stays at rest and where no pairs are broken, (B) a region where the pairs are progressively broken with increasing distance from the rotational axis, resulting in an increasing rotational current, and (C) a normal-fluid region where all pairs are broken and which rotates like a rigid body. Due to region B, density and current do not exhibit any discontinuities.Comment: 4 pages, 2 figures; v2: discussion clarified, typos corrected, one reference adde

Separable Structure of Many-Body Ground-State Wave Function

We have investigated a general structure of the ground-state wave function for the Schr\"odinger equation for $N$ identical interacting particles (bosons or fermions) confined in a harmonic anisotropic trap in the limit of large $N$. It is shown that the ground-state wave function can be written in a separable form. As an example of its applications, this form is used to obtain the ground-state wave function describing collective dynamics for $N$ trapped bosons interacting via contact forces.Comment: J. Phys. B: At. Mol. Opt. Phys. 33 (2000) (accepted for publication

Magnetic and transport properties of rare-earth-based half-Heusler phases RPdBi: prospective systems for topological quantum phenomena

RPdBi (R = Er, Ho, Gd, Dy, Y, Nd) compounds were studied by means of x-ray diffraction, magnetic susceptibility, electrical resistivity, magnetoresistivity, thermoelectric power and Hall effect measurements, performed in the temperature range 1.5-300 K and in magnetic fields up to 12 T. These ternaries, except diamagnetic YPdBi, exhibit localized magnetism of $R^{3+}$ ions, and order antiferromagnetically at low temperatures ($T_{N}$ = 2-13 K). The transport measurements revealed behavior characteristic of semimetals or narrow-band semiconductors. Both, electrons and holes contribute to the conductivity with dominant role of p-type carriers. The Hall effect of ErPdBi is strongly temperature and magnetic field dependent, reflecting complex character of the underlying electronic structures with multiple electron and hole bands. RPdBi, and especially DyPdBi, exhibit very good thermoelectric properties with a power factor coefficient $PF$ ranging from 6 to 20 $\mu$Wcm$^{-1}$K$^{-2}$.Comment: 6 pages, 5 figures; Accepted to Physical Review B (June 17, 2011

Inertial parameters and superfluid-to-normal phase transition in superdeformed bands

The quasiclassically exact solution for the second inertial parameter $\cal B$ is found in self-consistent way. It is shown that superdeformation and nonuniform pairing arising from the rotation induced pair density significantly reduce this inertial parameter. The different limiting cases for $\cal B$, which allow to study an interplay between rapid rotation, pairing correlations, and mean field deformation, are considered. The new signature for the transition from pairing to normal phase is suggested in terms of the variation of ${\cal B}/{\cal A}$ versus spin. Experimental data indicate the existence of such transition in the three superdeformed mass regions.Comment: 8 pages, LaTeX, 3 figure

Electronic structure of SrPt_4Ge_{12}: a combined photoelectron spectroscopy and band structure study

We present a combined study of the electronic structure of the superconducting skutterudite derivative SrPt4Ge12 by means of X-ray photoelectron spectroscopy and full potential band structure calculations including an analysis of the chemical bonding. We establish that the states at the Fermi level originate predominantly from the Ge 4p electrons and that the Pt 5d shell is effectively full. We find excellent agreement between the measured and the calculated valence band spectra, thereby validating that band structure calculations in combination with photoelectron spectroscopy can provide a solid basis for the modeling of superconductivity in the compounds MPt4Ge12 (M = Sr, Ba, La, Pr) series

Impact of temperature and mode polarization on the acoustic phonon range in complex crystalline phases: A case study on intermetallic clathrates

The low and weakly temperature-varying lattice thermal conductivity, κL (T), in crystals with a complex unit cell such as type-I clathrates is assumed to originate from a reduced momentum and energy space available for propagative lattice vibrations, which is caused by the occurrence of low-energy optical phonon modes. In the context of ab initio self-consistent phonon (SCP) theory, it has been shown that the cubic and quartic anharmonic interactions result in a temperature-induced energy renormalization of these low-lying optical branches which contributes to the anomalous behavior of κL (T) in structurally ordered type-I clathrates [T. Tadano and S. Tsuneyuki, Phys. Rev. Lett. 120, 105901 (2018)]. By means of inelastic neutron scattering, we provide evidence for this energy renormalization in temperature, which has been resolved for transversely and longitudinally polarized phonons in the single crystal type-I clathrate Ba7.81Ge40.67Au5.33. By mapping the neutron intensity in the momentum space, we demonstrate the coherent character of the low-lying optical phonons. The overall phonon spectrum and dynamical structure factors are satisfactorily reproduced by ab initio harmonic calculations using density functional theory with the meta-GGA SCAN functional and a fully ordered structure. However, a polarization-dependent cutoff energy with opposing temperature shifts for longitudinal and transverse acoustic dispersions is experimentally observed which is not reproduced by the simulations. Anharmonicity affects the energies of the low-lying optical phonons in the transverse polarization, which compares quantitatively well with available results from SCP theory, whereas differences are observed for the longitudinal polarizatio

Superfluid to normal phase transition and extreme regularity of superdeformed bands

We derive the exact semiclassical expression for the second inertial parameter $\cal B$ for the superfluid and normal phases. Interpolation between these limiting values shows that the function ${\cal B}(I)$ changes sign at the spin $I_c$, which is critical for a rotational spectrum. The quantity $\cal B$ turns out to be a sensitive measure of the change in static pairing correlations. The superfluid-to-normal transition reveals itself in the specific variation of the ratio ${\cal B}/{\cal A}$ versus spin $I$ with the plateau characteristic of the normal phase. We find this dependence to be universal for normal deformed and superdeformed bands. The long plateau with a small value ${\cal B}/{\cal A}\sim A^{-8/3}$ explains the extreme regularity of superdeformed bands.Comment: 30 pages in LaTeX, 6 figures (PostScript). To be published in Yadernaya Fizika (Physics of Atomic Nuclei), special edition dedecated to the 90th birthday of Prof. I. I. Gurevit

Giant penile melanoma

Primary penile melanoma is an extremely rare casuistic pathology associated with a poor prognosis. The article presents a clinical case of massive lesion of the penis with malignant melanoma, and discusses surgical methods for treating this pathology

Современные подходы к таргетной биопсии предстательной железы

Prostate cancer (PCa) is in second place in oncological morbidity in males and is the fifth leading cause of death among the world's population. According to current world statistics, over the past 20 years there has been an increase in primary morbidity, as well as mortality from PCa. The key to diagnosing PCa is a prostate biopsy. Nevertheless, a systemic biopsy under transrectal ultrasound control is the subject of discussion and debate in oncourology, as it has significant drawbacks that affect the qualitative result of the diagnosis of PCa. Given the importance of adequate and staged PCa, various methods of targeted biopsy under magnetic resonance control have been proposed.This review will examine the main features and significance of targeted prostate biopsy, as well as the role of magnetic resonance imaging in the early diagnosis of PCa. The method of targeted biopsy of the prostate gland can improve the detection of PCa in relation to clinically significant forms. In addition, this method is extremely promising and requires further study to further improve the quality of early diagnosis of PCa, especially when selecting patients for radical surgical treatment.Рак предстательной железы (РПЖ) занимает 2-е место в структуре онкологической заболеваемости мужчин и 5-е место среди причин смерти населения в мире. Согласно данным мировой статистики в течение последних 20 лет отмечается рост первичной заболеваемости РПЖ, а также смертности от него. Основным методом диагностики РПЖ является биопсия предстательной железы. Тем не менее системная биопсия под трансректальным ультразвуковым контролем остается предметом дискуссии в онкоурологии, так как имеет значимые недостатки, которые влияют на качественный результат диагностики РПЖ. С учетом важности стадирования данного заболевания были предложены различные способы прицельной биопсии под магнитно-резонансным контролем.В настоящем обзоре рассмотрены основные особенности и значимость таргетной биопсии предстательной железы, а также роль магнитно-резонансной томографии в ранней диагностике РПЖ. Таргетная биопсия предстательной железы позволяет улучшить показатели выявления РПЖ в отношении клинически значимых форм. Данный способ является крайне перспективным и требует дальнейшего изучения для дальнейшего повышения качества ранней диагностики РПЖ, особенно при отборе пациентов для радикального хирургического лечения