Active control of qubit-qubit entanglement evolution

In this work, we propose a scheme to design the time evolution of the entropy of entanglement between two qubits. It is shown an explicit accurate solution for the inverse problem of determining the time dependence of the coupling constant from a user-defined dynamical entanglement function. Such an active control of entanglement can be implemented in many different physical implementations of coupled qubits, and we briefly comment on the use of interacting flux qubits.Comment: Author added, Expanded version, 10 figure

Energy dependence of ϕ meson production at forward rapidity in pp collisions at the LHC

The production of $\phi$ mesons has been studied in pp collisions at LHC energies with the ALICE detector via the dimuon decay channel in the rapidity region $2.5< y < 4$. Measurements of the differential cross section $\mathrm{d}^2\sigma /\mathrm{d}y \mathrm{d}p_{\mathrm {T}}$ are presented as a function of the transverse momentum ($p_{\mathrm {T}}$) at the center-of-mass energies $\sqrt{s}=5.02$, 8 and 13 TeV and compared with the ALICE results at midrapidity. The differential cross sections at $\sqrt{s}=5.02$ and 13 TeV are also studied in several rapidity intervals as a function of $p_{\mathrm {T}}$, and as a function of rapidity in three $p_{\mathrm {T}}$ intervals. A hardening of the $p_{\mathrm {T}}$-differential cross section with the collision energy is observed, while, for a given energy, $p_{\mathrm {T}}$ spectra soften with increasing rapidity and, conversely, rapidity distributions get slightly narrower at increasing $p_{\mathrm {T}}$. The new results, complementing the published measurements at $\sqrt{s}=2.76$ and 7 TeV, allow one to establish the energy dependence of $\phi$ meson production and to compare the measured cross sections with phenomenological models. None of the considered models manages to describe the evolution of the cross section with $p_{\mathrm {T}}$ and rapidity at all the energies.publishedVersio

Cluster-type Entangled Coherent States

We present the cluster-type entangled coherent states (CTECS) and discuss their properties. A cavity QED generation scheme using suitable choices of atom-cavity interactions, obtained via detunings adjustments and the application of classical external fields, is also presented. After the realization of simple atomic measurements, CTECS representing nonlocal electromagnetic fields in separate cavities can be generated. © 2008 Elsevier B.V. All rights reserved.3722035803585Briegel, H.J., Raussendorf, R., (2001) Phys. Rev. Lett., 86, p. 910Raussendorf, R., Briegel, H.J., (2001) Phys. Rev. Lett., 86, p. 5188Raussendorf, R., Browne, D.E., Briegel, H.J., (2002) J. Mod. Opt., 49, p. 1299Raussendorf, R., Browne, D.E., Briegel, H.J., (2003) Phys. Rev. A, 68, p. 022312Nielsen, M.A., Chuang, I.L., (2000) Quantum Computation and Quantum Information, , Cambridge Univ. 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The Entanglement Of Two Dipole-dipole Coupled Atoms In A Cavity Interacting With A Thermal Field

We investigate the entanglement properties of a system of two dipole-dipole coupled two-level atoms resonantly interacting with a thermal field in a high-Q cavity. We obtain the evolution operator for this system in an analytical form, and use it to evaluate the atom-atom entanglement through the calculation of the negativity. We find that, despite the destructive effect of thermal noise, the dipole interaction yields a considerable amount of entanglement between the two atoms. © 2005 IOP Publishing Ltd.712S769S771Bose, S., Fuentes-Guridi, I., Knight, P.L., Vedral, V., (2001) Phys. Rev. Lett., 87 (5), p. 050401Kim, M.S., Lee, J., Ahn, D., Knight, P.L., (2002) Phys. Rev., 65 (4), p. 040101Tanaś, R., Ficek, Z., (2004) J. Opt. B: Quantum Semiclass. Opt., 6 (3), p. 90Peng, J.S., Li, G.X., (1993) Phys. Rev., 47 (5), p. 4212Peres, A., (1996) Phys. Rev. Lett., 77 (8), p. 1413Wooters, W.K., (1998) Phys. Rev. Lett., 80 (10), p. 224

Probability of major depression classification based on the SCID, CIDI, and MINI diagnostic interviews: A synthesis of three individual participant data meta-analyses

Introduction: Three previous individual participant data meta-analyses (IPDMAs) reported that, compared to the Structured Clinical Interview for the DSM (SCID), alternative reference standards, primarily the Composite International Diagnostic Interview (CIDI) and the Mini International Neuropsychiatric Interview (MINI), tended to misclassify major depression status, when controlling for depression symptom severity. However, there was an important lack of precision in the results. Objective: To compare the odds of the major depression classification based on the SCID, CIDI, and MINI. Methods: We included and standardized data from 3 IPDMA databases. For each IPDMA, separately, we fitted binomial generalized linear mixed models to compare the adjusted odds ratios (aORs) of major depression classification, controlling for symptom severity and characteristics of participants, and the interaction between interview and symptom severity. Next, we synthesized results using a DerSimonian-Laird random-effects meta-analysis. Results: In total, 69,405 participants (7,574 [11%] with major depression) from 212 studies were included. Controlling for symptom severity and participant characteristics, the MINI (74 studies; 25,749 participants) classified major depression more often than the SCID (108 studies; 21,953 participants; aOR 1.46; 95% confidence interval [CI] 1.11-1.92]). Classification odds for the CIDI (30 studies; 21,703 participants) and the SCID did not differ overall (aOR 1.19; 95% CI 0.79-1.75); however, as screening scores increased, the aOR increased less for the CIDI than the SCID (interaction aOR 0.64; 95% CI 0.52-0.80). Conclusions: Compared to the SCID, the MINI classified major depression more often. The odds of the depression classification with the CIDI increased less as symptom levels increased. Interpretation of research that uses diagnostic interviews to classify depression should consider the interview characteristics. © 202

Using global team science to identify genetic Parkinson's disease worldwide

Talks on rare diseases in the field of neurology often start with a statement like this: “About 80% of all rare diseases have a neurologic manifestation and about 80% of those are genetic in origin.” Although these numbers probably represent more of an estimate than well‐documented evidence, rapidly advancing and cost‐effective sequencing technologies have led to the quickly growing identification of patients with hereditary neurological diseases..