Spatial Coherence of a Polariton Condensate

We perform Young's double-slit experiment to study the spatial coherence properties of a two-dimensional dynamic condensate of semiconductor microcavity polaritons. The coherence length of the system is measured as a function of the pump rate, which confirms a spontaneous buildup of macroscopic coherence in the condensed phase. An independent measurement reveals that the position and momentum uncertainty product of the condensate is close to the Heisenberg limit. An experimental realization of such a minimum uncertainty wave packet of the polariton condensate opens a door to coherent matter-wave phenomena such as Josephson oscillation, superfluidity, and solitons in solid state condensate systems

Quantum Degenerate Exciton-Polaritons in Thermal Equilibrium

We study the momentum distribution and relaxation dynamics of semiconductor microcavity polaritons by angle-resolved and time-resolved spectroscopy. Above a critical pump level, the thermalization time of polaritons at positive detunings becomes shorter than their lifetime, and the polaritons form a quantum degenerate Bose-Einstein distribution in thermal equilibrium with the lattice.Comment: Updated with the published versio

Информационная система учёта и анализа услуг ветеринарной клиники ООО "ТАМАСИНА".

Объектом исследования является деятельность ООО "ТАМАСИНА" по оказанию ветеринарных услуг населению нашему городу. Цель работы – проектирование информационной система учёта и анализа услуг ветеринарной клиники ООО "ТАМАСИНА". В процессе исследования проводился теоретический анализ, обзор аналогов, проектирование и разработка информационной системы. В результате разработана информационная система, реализующая основные функции: учет клиентов клиники; учет оказанных услуг; учет расхода лекарственных препаратов; анализ оказания услуг. Область применения: оказание ветеринарных услуг, реклама, учет клиентов ветеринарной клиники, информирование населения о деятельности организации, осуществление обратной связи с клиентами.The object of the study is the activity of LLC "TAMASINA" in providing veterinary services to the population of our city. The purpose of the work is the design of the information system for accounting and analysis of the services of the veterinary clinic of LLC "TAMASINA". In the process of the research, a theoretical analysis, a review of analogues, design and development of an information system were carried out. As a result, the educational system that implements the main functions: the account of the clients of the clinic; Accounting services provided; Accounting for medicines soon; Analysis of the provision of services. Scope: the provision of veterinary services, advertising, accounting of customers of veterinary clinics

Mesoscopic spin confinement during acoustically induced transport

Long coherence lifetimes of electron spins transported using moving potential dots are shown to result from the mesoscopic confinement of the spin vector. The confinement dimensions required for spin control are governed by the characteristic spin-orbit length of the electron spins, which must be larger than the dimensions of the dot potential. We show that the coherence lifetime of the electron spins is independent of the local carrier densities within each potential dot and that the precession frequency, which is determined by the Dresselhaus contribution to the spin-orbit coupling, can be modified by varying the sample dimensions resulting in predictable changes in the spin-orbit length and, consequently, in the spin coherence lifetime.Comment: 10 pages, 2 figure

Magneto-transport in periodic and quasiperiodic arrays of mesoscopic rings

We study theoretically the transmission properties of serially connected mesoscopic rings threaded by a magnetic flux. Within a tight-binding formalism we derive exact analytical results for the transmission through periodic and quasiperiodic Fibonacci arrays of rings of two different sizes. The role played by the number of scatterers in each arm of the ring is analyzed in some detail. The behavior of the transmission coefficient at a particular value of the energy of the incident electron is studied as a function of the magnetic flux (and vice versa) for both the periodic and quasiperiodic arrays of rings having different number of atoms in the arms. We find interesting resonance properties at specific values of the flux, as well as a power-law decay in the transmission coefficient as the number of rings increases, when the magnetic field is switched off. For the quasiperiodic Fibonacci sequence we discuss various features of the transmission characteristics as functions of energy and flux, including one special case where, at a special value of the energy and in the absence of any magnetic field, the transmittivity changes periodically as a function of the system size.Comment: 9 pages with 7 .eps figures included, submitted to PR

Erforschung eines diodengepumpten (Multi-core) M-Profil-Faserlasers im Ultrakurzpulsbetrieb, Unterauftrag: Entwicklung eines Halbleiter-Bauelementes aus Bragg-Reflektoren, sättigbarem Absorber und 2-Photonen-Absorber : Abschlußbericht über das F&E-Vorhaben

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Unrechtsurteile der NS-Zeit

Kempny S. Unrechtsurteile der NS-Zeit. In: Drüen K-D, Hey J, Mellinghoff R, eds. 100 Jahre Steuerrechtsprechung in Deutschland. Festschrift für den Bundesfinanzhof. Vol 1. Köln: Dr. Otto Schmidt; 2018: 39-58

Ultrafast Nonlinear Terahertz Studies of High-Field Charge Transport in Semiconductors

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