Design of photonic crystal microcavities for cavity QED

We discuss the optimization of optical microcavity designs based on 2D photonic crystals for the purpose of strong coupling between the cavity field and a single neutral atom trapped within a hole. We present numerical predictions for the quality factors and mode volumes of localized defect modes as a function of geometric parameters, and discuss some experimental challenges related to the coupling of a defect cavity to gas-phase atoms.Comment: 12 pages, 16 figure

Alcoholism and Depression

Alcoholism and depression are entangled in many ways and appear in many combinations. In spite of this fact, to this problem is rarely given sufficient attention which results in poor diagnostic and inadequate therapeutic approach with all the consequences this engenders. The frequency of depression in alcoholics is investigated here with the object of finding out to what extent it can be successfully diagnosed and medically treated. The research was carried out in the Psychiatric Clinic of the Clinical Hospital »Split« and the sample of examinees included the patients treated in the stationary part of the Clinic and in the daily hospital

Regiospecific Synthesis and X-ray Structural Study of Trifluoromethyl Substituted Dibenzosemibullvalene

Preparation of the novel regiospecifically trifluoromethyl substituted dibenzobarrelene 5 and dibenzosemibullvalene 6 is described. Unequivocal proof for the stereostructure of 6 was obtained by its X-ray crystallographic analysis. Geometrical data from X-ray structural analysis showed that the ester carbonyl groups adopt unfavorable conformations for conjugative interactions with respect to the cyclopropane ring involved in the skeleton of 6

Difference-frequency generation with quantum-limited efficiency in triply-resonant nonlinear cavities

We present a comprehensive study of second-order nonlinear difference frequency generation in triply resonant cavities using a theoretical framework based on coupled-mode theory. We show that optimal quantum-limited conversion efficiency can be achieved at any pump power when the powers at the pump and idler frequencies satisfy a critical relationship. We demonstrate the existence of a broad parameter range in which all triply-resonant DFG processes exhibit monostable conversion. We also demonstrate the existence of a geometry-dependent bistable region.Comment: 10 pages, 3 figure

Event-shape and multiplicity dependence of freeze-out radii in pp collisions at √s = 7 TeV

Two-particle correlations in high-energy collision experiments enable the extraction of particle source radii by using the Bose-Einstein enhancement of pion production at low relative momentum q ∝ 1/R. It was previously observed that in pp collisions at √s = 7TeV the average pair transverse momentum kT range of such analyses is limited due to large background correlations which were attributed to mini-jet phenomena. To investigate this further, an event-shape dependent analysis of Bose-Einstein correlations for pion pairs is performed in this work. By categorizing the events by their transverse sphericity ST into spherical (ST > 0:7) and jet-like (ST < 0:3) events a method was developed that allows for the determination of source radii for much larger values of kT for the first time. Spherical events demonstrate little or no background correlations while jet-like events are dominated by them. This observation agrees with the hypothesis of a mini-jet origin of the non-femtoscopic background correlations and gives new insight into the physics interpretation of the kT dependence of the radii. The emission source size in spherical events shows a substantially diminished kT dependence, while jet-like events show indications of a negative trend with respect to kT in the highest multiplicity events. Regarding the emission source shape, the correlation functions for both event sphericity classes show good agreement with an exponential shape, rather than a Gaussian one

Photon-mediated interactions between quantum emitters in a diamond nanocavity

Photon-mediated interactions between quantum systems are essential for realizing quantum networks and scalable quantum information processing. We demonstrate such interactions between pairs of silicon-vacancy (SiV) color centers coupled to a diamond nanophotonic cavity. When the optical transitions of the two color centers are tuned into resonance, the coupling to the common cavity mode results in a coherent interaction between them, leading to spectrally-resolved superradiant and subradiant states. We use the electronic spin degrees of freedom of the SiV centers to control these optically-mediated interactions. Such controlled interactions will be crucial in developing cavity-mediated quantum gates between spin qubits and for realizing scalable quantum network nodes

Monolithic integrated-optic TDLAS sensors

ABSTRACT We are developing prototype chip-scale low-power integrated-optic gas-phase chemical sensors based on infrared Tunable Diode Laser Absorption Spectroscopy (TDLAS). TDLAS is able to sense many gas phase chemicals with high sensitivity and selectivity. Using semiconductor fabrication and assembly techniques, the low-cost integrated optic TDLAS technology will permit mass production of sensors that have wide ranging industrial, medical, environmental, and consumer applications. Novel gas sensing elements using low-loss resonant photonic crystal cavities or waveguides will permit monolithic integration of a laser source, sampling elements, and detector on a semiconductor materials system substrate. Practical challenges to fabricating these devices include: a) selecting and designing the high-Q microresonator sensing element appropriate for the selected analyte; and b) device thermal management, especially stabilizing laser temperature with the precision needed for sensitive spectroscopic detection. In this paper, we analyze the expected sensitivity of micro-resonator-based structures for chemical sensing, and demonstrate a novel approach for exploiting laser waste heat to stabilize the laser temperature

Weather Conditions Influence on Lavandin Essential Oil and Hydrolate Quality

Lavandula sp. essential oil and hydrolate are commercially valuable in various industry branches with the potential for wide-ranging applications. This study aimed to evaluate the quality of these products obtained from L. x intermedia cv. ‘Budrovka’ for the first time cultivated on Fruška Gora Mt. (Serbia) during three successive seasons (2019, 2020, and 2021). Essential oil extraction was obtained by steam distillation, and the composition and influence of weather conditions were also assessed, using flowering tops. The obtained essential oils and hydrolates were analysed by gas chromatography with a flame ionization detector (GC-FID) and gas chromatography coupled to mass spectrometry (GC-MS). A linear regression model was developed to predict L. x intermedia cv. ‘Budrovka’ essential oil volatile compound content and hydrolate composition during three years, according to temperature and precipitation data, and the appropriate regression coefficients were calculated, while the correlation analysis was employed to analyse the correlations in hydrolate and essential oil compounds. To completely describe the structure of the research data that would present a better insight into the similarities and differences among the diverse L. x intermedia cv. ‘Budrovka’ samples, the PCA was used. The most dominant in L. intermedia cv. ‘Budrovka’ essential oil and hydrolate were oxygenated monoterpenes: linalool, 1,8-cineole, borneol, linalyl acetate, and terpinene-4-ol. It is established that the temperature was positively correlated with all essential oil and hydrolate compounds. The precipitations were positively correlated with the main compounds (linalool, 1,8-cineole, and borneol), while the other compounds’ content negatively correlated to precipitation. The results indicated that Fruška Gora Mt. has suitable agro-ecological requirements for cultivating Lavandula sp. and providing satisfactory essential oil and hydrolate. © 2022 by the authors. Licensee MDPI, Basel, Switzerland