Comparison of 87Rb N-resonances for D1 and D2 transitions

We report an experimental comparison of three-photon-absorption resonances (known as "N-resonances") for the D_1 and D_2 optical transitions of thermal 87Rb vapor. We find that the D_2 N-resonance has better contrast, a broader linewidth, and a more symmetric lineshape than the D_1 N-resonance. Taken together, these factors imply superior performance for frequency standards operating on alkali D_2 N-resonances, in contrast to coherent population trapping (CPT) resonances for which the D_2 transition provides poorer frequency standard performance than the D_1 transition.Comment: 3 pages, 4 figure

РОЛЬ СУЧАСНИХ ІНФОРМАЦІЙНИХ ТЕХНОЛОГІЙ У ЗАБЕЗПЕЧЕННІ ЯКОСТІ МЕДИЧНОЇ ОСВІТИ

The aim of the work –  to improve the quality of medical education through the use of modern information technologies. The main body. The article presents the role of modern information technologies in ensuring the quality of medical education. The reform of the health care system requires consistent changes in the training of a modern specialist with an appropriate level of competence, knowledge of the theoretical knowledge and practical skills prepared for market relations in the field of medical services provision. One of the most important prerequisites for ensuring the quality of higher medical education is the introduction of a new level of e-learning or “open learning” in the educational process, which is especially important for the training of a modern specialist. Conclusion. In order to improve the quality of medical education, it is necessary to take into account certain peculiarities of medical e-education, in particular its practical content, standardization of decision-making in the medical and diagnostic direction (protocols of medical aid provision), strengthening of the requirements for acquiring skills of the manager of the medical industry, readiness for work in the labor market and medical services.Мета роботи – з’ясувати вплив інформаційних технологій у трансформації післядипломної медичної освіти. Основна частина. У статті наведено роль сучасних інформаційних технологій у  забезпеченні якості медичної освіти. Реформа системи охорони здоров’я потребує послідовних змін у підготовці сучасного фахівця з належним рівнем компетентностей, володіння теоретичними знаннями та практичними навичками, підготовленого до ринкових відносин у питаннях надання медичних послуг. Однією з важливих передумов забезпечення якості вищої медичної освіти є впровадження в навчальний процес електронної освіти (e-learning) нового рівня або «відкритого навчання», що є особливо важливим для підготовки сучасного фахівця. Висновок. З метою поліпшення якості медичної освіти необхідне урахування певних особливостей медичної електронної освіти, зокрема її практично-орієнтованого змісту, стандартизації прийняття рішень лікувально-діагностичного спрямування (протоколи надання медичної допомоги), посилення вимог до набуття навичок менеджера медичної галузі, готовності до роботи на ринку праці та медичних послуг

Selective addressing of high-rank atomic polarization moments

We describe a method of selective generation and study of polarization moments of up to the highest rank $\kappa=2F$ possible for a quantum state with total angular momentum $F$. The technique is based on nonlinear magneto-optical rotation with frequency-modulated light. Various polarization moments are distinguished by the periodicity of light-polarization rotation induced by the atoms during Larmor precession and exhibit distinct light-intensity and frequency dependences. We apply the method to study polarization moments of $^{87}$Rb atoms contained in a vapor cell with antirelaxation coating. Distinct ultra-narrow (1-Hz wide) resonances, corresponding to different multipoles, appear in the magnetic-field dependence of the optical rotation. The use of the highest-multipole resonances has important applications in quantum and nonlinear optics and in magnetometry.Comment: 5 pages, 6 figure

Optical properties of atomic Mott insulators: from slow light to dynamical Casimir effects

We theoretically study the optical properties of a gas of ultracold, coherently dressed three-level atoms in a Mott insulator phase of an optical lattice. The vacuum state, the band dispersion and the absorption spectrum of the polariton field can be controlled in real time by varying the amplitude and the frequency of the dressing beam. In the weak dressing regime, the system shows unique ultra-slow light propagation properties without absorption. In the presence of a fast time modulation of the dressing amplitude, we predict a significant emission of photon pairs by parametric amplification of the polaritonic zero-point fluctuations. Quantitative considerations on the experimental observability of such a dynamical Casimir effect are presented for the most promising atomic species and level schemes

Trace formula for dielectric cavities II: Regular, pseudo-integrable, and chaotic examples

Dielectric resonators are open systems particularly interesting due to their wide range of applications in optics and photonics. In a recent paper [PRE, vol. 78, 056202 (2008)] the trace formula for both the smooth and the oscillating parts of the resonance density was proposed and checked for the circular cavity. The present paper deals with numerous shapes which would be integrable (square, rectangle, and ellipse), pseudo-integrable (pentagon) and chaotic (stadium), if the cavities were closed (billiard case). A good agreement is found between the theoretical predictions, the numerical simulations, and experiments based on organic micro-lasers.Comment: 18 pages, 32 figure

An insight into polarization states of solid-state organic lasers

The polarization states of lasers are crucial issues both for practical applications and fundamental research. In general, they depend in a combined manner on the properties of the gain material and on the structure of the electromagnetic modes. In this paper, we address this issue in the case of solid-state organic lasers, a technology which enables to vary independently gain and mode properties. Different kinds of resonators are investigated: in-plane micro-resonators with Fabry-Perot, square, pentagon, stadium, disk, and kite shapes, and external vertical resonators. The degree of polarization P is measured in each case. It is shown that although TE modes prevail generally (P>0), kite-shaped micro-laser generates negative values for P, i.e. a flip of the dominant polarization which becomes mostly TM polarized. We at last investigated two degrees of freedom that are available to tailor the polarization of organic lasers, in addition to the pump polarization and the resonator geometry: upon using resonant energy transfer (RET) or upon pumping the laser dye to an higher excited state. We then demonstrate that significantly lower P factors can be obtained.Comment: 12 pages, 12 figure

Slow Light Propagation in a Thin Optical Fiber via Electromagnetically Induced Transparency

We propose a novel configuration that utilizes electromagnetically induced transparency (EIT) to tailor a fiber mode propagating inside a thin optical fiber and coherently control its dispersion properties to drastically reduce the group velocity of the fiber mode. The key to this proposal is: the evanescent-like field of the thin fiber strongly couples with the surrounding active medium, so that the EIT condition is met by the medium. We show how the properties of the fiber mode is modified due to the EIT medium, both numerically and analytically. We demonstrate that the group velocity of the new modified fiber mode can be drastically reduced (approximately 44 m/sec) using the coherently prepared orthohydrogen doped in a matrix of parahydrogen crystal as the EIT medium.Comment: 10 pages in two column RevTex4, 6 Figure

Temperature measurement and stabilization in a birefringent whispering gallery resonator

Temperature measurement with nano-Kelvin resolution is demonstrated at room temperature, based on the thermal dependence of an optical crystal anisotropy in a high quality whispering gallery resonator. As the resonator's TE and TM modes frequencies have different temperature coefficients, their differential shift provides a sensitive measurement of the temperature variation, which is used for active stabilization of the temperature

Conversion of conventional gravitational-wave interferometers into QND interferometers by modifying their input and/or output optics

The LIGO-II gravitational-wave interferometers (ca. 2006--2008) are designed to have sensitivities at about the standard quantum limit (SQL) near 100 Hz. This paper describes and analyzes possible designs for subsequent, LIGO-III interferometers that can beat the SQL. These designs are identical to a conventional broad-band interferometer (without signal recycling), except for new input and/or output optics. Three designs are analyzed: (i) a "squeezed-input interferometer" (conceived by Unruh based on earlier work of Caves) in which squeezed vacuum with frequency-dependent (FD) squeeze angle is injected into the interferometer's dark port; (ii) a "variational-output" interferometer (conceived in a different form by Vyatchanin, Matsko and Zubova), in which homodyne detection with FD homodyne phase is performed on the output light; and (iii) a "squeezed-variational interferometer" with squeezed input and FD-homodyne output. It is shown that the FD squeezed-input light can be produced by sending ordinary squeezed light through two successive Fabry-Perot filter cavities before injection into the interferometer, and FD-homodyne detection can be achieved by sending the output light through two filter cavities before ordinary homodyne detection. With anticipated technology and with laser powers comparable to that planned for LIGO-II, these interferometers can beat the amplitude SQL by factors in the range from 3 to 5, corresponding to event rate increases between ~30 and ~100 over the rate for a SQL-limited interferometer.Comment: Submitted to Physical Review D; RevTeX manuscript with 16 figures; prints to 33 pages in Physical Review double column format. Minor revisions have been made in response to referee repor