5,079 research outputs found
Pure single photon generation by type-I PDC with backward-wave amplification
We explore a promising method of generating pure heralded single photons. Our
approach is based on parametric downconversion in a periodically-poled
waveguide. However, unlike conventional downconversion sources, the photon
pairs are counter-propagating: one travels with the pump beam in the forward
direction while the other is backpropagating towards the laser source. Our
calculations reveal that these downconverted two-photon states carry minimal
spectral correlations within each photon-pair. This approach offers the
possibility to employ a new range of downconversion processes and materials
like PPLN (previously considered unsuitable due to their unfavorable
phasematching properties) to herald pure single photons over a broad frequency
range.Comment: 8 pages, 3 figures, minor text changes and reformattin
decays and twisted boundary conditions
We propose a new method to evaluate the Lellouch-L\"uscher factor which
relates the matrix elements computed on a finite
lattice to the physical (infinite-volume) decay amplitudes. The method relies
on the use of partially twisted boundary conditions, which allow the s-wave
phase shift to be computed as an almost continuous function of the
centre-of-mass relative momentum and hence for its derivative to be evaluated.
We successfully demonstrate the feasibility of the technique in an exploratory
computation.Comment: 19 pages, 7 figure
Proses Derivasi dalam Bahasa Biak
Bahasa Biak adalah salah satu bahasa Austronesia yang luas sebarannya di bagian utara Papua dengan jumlah penutur kurang lebih 50.000 – 70.000 orang. Bahasa ini memiliki proses derivasi yang unik karena (1) hanya terdapat pada verba dan adjektiva yang berubah menjadi nomina, (2) pada umumnya verba dan adjektiva yang memiliki dua sampai tiga suku kata, (3) proses derivasi berkaitan dengan suku kata, (4) derivasi kata terjadi dengan penggabungan morfem <a> dalam suku kata dengan berbagai alomorf, (5) hasil proses derivasi berbentuk reduplikasi atau pengulangan yang rumit namun di Balik itu ada keteraturan, terutama pada kata-kata yang bersuku satu dan dua
Effects of finite volume on the KL-KS mass difference
Phenomena that involve two or more on-shell particles are particularly sensitive to the effects of finite volume and require special treatment when computed using lattice QCD. In this paper we generalize the results of Lüscher and Lellouch and Lüscher, which determine the leading-order effects of finite volume on the two-particle spectrum and two-particle decay amplitudes to determine the finite-volume effects in the second-order mixing of the K0 and K0¯ states. We extend the methods of Kim, Sachrajda, and Sharpe to provide a direct, uniform treatment of these three, related, finite-volume corrections. In particular, the leading, finite-volume corrections to the KL-KS mass difference ΔMK and the CP-violating parameter εK are determined, including the potentially large effects which can arise from the near degeneracy of the kaon mass and the energy of a finite-volume, two-pion state
The Contribution of a Polygenic Risk Score to Individual Differences in Aggressive Behavior: The Moderating and Mediating Roles of Stressful Events
Although aggression can be beneficial in certain situations (e.g. playing sports, self-defense), excessive and inappropriate aggression can lead to adverse physical and psychological health outcomes in both perpetrators and victims. Genetic susceptibility to negative environments can increase the likelihood of aggressive behavior in the context of situational risk factors. Low efficiency of serotonin neurotransmission and exposure to stress appear to play a prominent role in the etiology of aggressive behavior. A set of three studies assessed the contribution of polygenic risk (TPH2 rs4570625, SLC6A4 5-HTTLPR+rs25531, HTR1B rs13212041, MAOA uVNTR) to aggressive behavior, including alcohol-related aggression, in university students at varying reported levels of childhood stress (i.e. exposure to childhood trauma, lack of social support). Additionally, the mediating role of acute stress on the association between the polygenic risk score and aggression was examined using both self-report measures and experimental manipulation. It was expected that increased genetic susceptibility would predict higher aggressive behavior resulting from stress, and that the association would be greater as level of exposure to childhood stress increased. Hypotheses for the study were partially supported. Findings showed that individuals with higher genetic susceptibility (i.e. high polygenic risk score) reported engaging in more aggression if they reported experiencing higher levels of childhood trauma and reported engaging in less aggression if they reported experiencing lower levels of childhood trauma. In women only, higher genetic susceptibility and higher reported levels of childhood trauma also predicted more aggression indirectly via higher acute perceived stress. However, these results did not generalize to alcohol-related aggression. The pattern of results is consistent with the Differential Susceptibility Model based on a visual inspection and suggests that individuals with genetic risk who have experienced childhood trauma may benefit from intervention and prevention strategies. Because the association in women between the polygenic risk score and aggression was mediated by stress, intervention and prevention strategies that focus on teaching adaptive coping techniques may be particularly useful in reducing aggressive behavior in women that occurs as a result of stress.
Adviser: Scott F. Stoltenber
Effective Quantum Dynamics of Interacting Systems with Inhomogeneous Coupling
We study the quantum dynamics of a single mode/particle interacting
inhomogeneously with a large number of particles and introduce an effective
approach to find the accessible Hilbert space where the dynamics takes place.
Two relevant examples are given: the inhomogeneous Tavis-Cummings model (e.g.,
N atomic qubits coupled to a single cavity mode, or to a motional mode in
trapped ions) and the inhomogeneous coupling of an electron spin to N nuclear
spins in a quantum dot.Comment: 9 pages and 10 figures, new version, accepted in Physical Review
Perancangan Buku Ilustrasi Batik Tuban sebagai Upaya Pelestarian Nilai-nilai Budaya
The emergence of the phenomenon of shifting cultural values contained in the motif by economic function raises concerns about the preservation of classic Indonesian batik motifs, especially the classic motifs of Tuban. Therefore, it takes a media design information in the form of book illustration to raise cultural values such as meaning, philosophy and myths contained in the classical batik Tuban. This design is done with the approach of observation, interviews and existing studies using the keyword viewpoint literature review results, namely the aesthetic, social, cultural, self-image and cultural products. By using descriptive-qualitative method of analysis that is supported by indicators STP and USP (Unique Selling Proposition) obtained "Covert charm" as a design concept and “Canting Batik Tuban" as the title of a book with manual drawing illustrations as main illustration. To determine the effectiveness, feasibility and suitability of the work used the test results of the questionnaire design through Likert scale. From the results of the correlation analysis of the design testing, it was found that all of the results of the questionnaire statements have a significant correlation so as to fulfill the purpose of the book value of the loading statement, 242- , 362 and the mean between 4.27 to 4.62
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