On a scale-invariant Fermi gas in a time-dependent harmonic potential

We investigate a scale-invariant two-component Fermi gas in a time-dependent isotropic harmonic potential. The exact time evolution of the density distribution in position space in any spatial dimension is obtained. Two experimentally relevant examples, an abrupt change and a periodic modulation of the trapping frequency are solved. Small deviations from scale invariance and isotropy of the confinement are addressed within first order perturbation theory. We discuss the consequences for experiments with ultracold quantum gases such as the excitation of a tower of undamped breathing modes and a new alternative for measuring the Tan contact.Comment: 6+3 pages, 2 figures; revised and extended versio

Державне управління якістю вищої освіти: менеджмент на рівні особистості

The article defined the directions of state management of the higher education quality, with taking into account peculiarities of manifestation (perception) of its contents on the individuality level. The article draws attention to the importance of aim to obtain higher education for ensuring its quality and also determined the place and role of the state in the corresponding process. In addition, the article determines the place and role of career guidance work in the system of higher education quality assurance, and presents a list of basic normative legal documents, which regulate relevant field of work. The article contains proposals for improving the normative legal mechanism of state management of the higher education quality.В статті визначено напрями державного управління якістю вищої освіти з прийняттям до уваги особливостей прояву (сприйняття) її змісту на індивідуальному рівні. В статті звернуто увагу на значущість мети здобуття вищої освіти для забезпечення її якості, а також визначено місце та роль держави у відповідному процесі. Крім того, стаття містить узагальнення щодо місця та ролі профорієнтаційної роботи в системі забезпечення якості вищої освіти, а також подано перелік основних нормативно-правових документів, які регламентують відповідний напрям роботи. Стаття містить пропозиції щодо вдосконалення нормативно-правового механізму державного управління якістю вищої освіти

Інститут корпоративного університету та його досвід для розвитку трудового потенціалу класичного вищого навчального закладу

This article focuses on some historical aspects of the formation and development of corporate training centers with taking into account the peculiarities of their functioning within a modern system of vocational education. In the article there is defined the categorical meaning of corporate education, and formulated the goal of corporate functioning of the institution. This article contains the author's opinion on the content of category definitions of corporate education and corporate university, and the results justify the importance of relevant experience of the Institute for the development of labor potential of classic form of higher education. In addition, the article presents generalizations about the possibility of using the traditional mechanisms of corporate universities to develop their own labor potential, within the system of classical universities in terms of improving the content of vocational training of subjects and objects of the educational process.Акцентується увага на окремих історичних аспектах формування та розвитку корпоративних навчальних центрів з прийняттям до уваги особливостей їх функціонування у межах сучасної системи професійної освіти. Визначено категоріальний зміст корпоративної освіти, а також сформульовано мету функціонування корпоративного навчального закладу. Викладено авторську думку щодо змісту визначень категорій корпоративної освіти та корпоративного університету, а також результати обґрунтування значущості досвіду функціонування відповідних інститутів для розвитку трудового потенціалу класичних за формою свого утворення вищих навчальних закладів. Наведено узагальнення щодо можливості використання традиційних для корпоративних університетів механізмів розвитку власного трудового потенціалу, у межах системи управління класичними вищими навчальними закладами в частині удосконалення змісту системи професійної підготовки суб’єктів та об’єктів навчально-виховного процесу

Generalized Efimov effect in one dimension

We study a one-dimensional quantum problem of two particles interacting with a third one via a scale-invariant subcritically attractive inverse square potential, which can be realized, for example, in a mixture of dipoles and charges confined to one dimension. We find that above a critical mass ratio, this version of the Calogero problem exhibits the generalized Efimov effect, the emergence of discrete scale invariance manifested by a geometric series of three-body bound states with an accumulation point at zero energy.Comment: 5+3 pages, 3 figures, published versio

Inward and Outward Integral Equations and the KKR Method for Photons

In the case of electromagnetic waves it is necessary to distinguish between inward and outward on-shell integral equations. Both kinds of equation are derived. A correct implementation of the photonic KKR method then requires the inward equations and it follows directly from them. A derivation of the KKR method from a variational principle is also outlined. Rather surprisingly, the variational KKR method cannot be entirely written in terms of surface integrals unless permeabilities are piecewise constant. Both kinds of photonic KKR method use the standard structure constants of the electronic KKR method and hence allow for a direct numerical application. As a by-product, matching rules are obtained for derivatives of fields on different sides of the discontinuity of permeabilities. Key words: The Maxwell equations, photonic band gap calculationsComment: (to appear in J. Phys. : Cond. Matter), Latex 17 pp, PRA-HEP 93/10 (exclusively English and unimportant misprints corrected

Voice morphing using the generative topographic mapping

In this paper we address the problem of Voice Morphing. We attempt to transform the spectral characteristics of a source speaker's speech signal so that the listener would believe that the speech was uttered by a target speaker. The voice morphing system transforms the spectral envelope as represented by a Linear Prediction model. The transformation is achieved by codebook mapping using the Generative Topographic Mapping, a non-linear, latent variable, parametrically constrained, Gaussian Mixture Model

How many orthonormal bases are needed to distinguish all pure quantum states?

We collect some recent results that together provide an almost complete answer to the question stated in the title. For the dimension d=2 the answer is three. For the dimensions d=3 and d>4 the answer is four. For the dimension d=4 the answer is either three or four. Curiously, the exact number in d=4 seems to be an open problem

Quantum phase transition in Bose-Fermi mixtures

We study a quantum Bose-Fermi mixture near a broad Feshbach resonance at zero temperature. Within a quantum field theoretical model a two-step Gaussian approximation allows to capture the main features of the quantum phase diagram. We show that a repulsive boson-boson interaction is necessary for thermodynamic stability. The quantum phase diagram is mapped in chemical potential and density space, and both first and second order quantum phase transitions are found. We discuss typical characteristics of the first order transition, such as hysteresis or a droplet formation of the condensate which may be searched for experimentally.Comment: 16 pages, 17 figures; typos corrected, one figure adde

Correlation functions for 1d interacting fermions with spin-orbit coupling

We compute correlation functions for one-dimensional electron systems which spin and charge degrees of freedom are coupled through spin-orbit coupling. Charge density waves, spin density waves, singlet- triplet- superconducting fluctuations are studied. We show that the spin-orbit interaction modify the exponents and the phase diagram of the system, changing the dominant fluctuations and making new susceptibilities diverge for low temperature.Comment: 5 pages, 3 figures. Accepted for publication in Phys. Rev.

Photonic crystals of coated metallic spheres

It is shown that simple face-centered-cubic (fcc) structures of both metallic and coated metallic spheres are ideal candidates to achieve a tunable complete photonic bandgap (CPBG) for optical wavelengths using currently available experimental techniques. For coated microspheres with the coating width to plasma wavelength ratio $l_c/\lambda_p \leq 10$ and the coating and host refractive indices $n_c$ and $n_h$, respectively, between 1 and 1.47, one can always find a sphere radius $r_s$ such that the relative gap width $g_w$ (gap width to the midgap frequency ratio) is larger than 5% and, in some cases, $g_w$ can exceed 9%. Using different coatings and supporting liquids, the width and midgap frequency of a CPBG can be tuned considerably.Comment: 14 pages, plain latex, 3 ps figures, to appear in Europhys. Lett. For more info on this subject see http://www.amolf.nl/research/photonic_materials_theory/moroz/moroz.htm