19,771 research outputs found
Pulse Width Modulation for Speeding Up Quantum Optimal Control Design
This paper focuses on accelerating quantum optimal control design for complex
quantum systems. Based on our previous work [{arXiv:1607.04054}], we combine
Pulse Width Modulation (PWM) and gradient descent algorithm into solving
quantum optimal control problems, which shows distinct improvement of
computational efficiency in various cases. To further apply this algorithm to
potential experiments, we also propose the smooth realization of the optimized
control solution, e.g. using Gaussian pulse train to replace rectangular
pulses. Based on the experimental data of the D-Norleucine molecule, we
numerically find optimal control functions in -qubit and -qubit systems,
and demonstrate its efficiency advantage compared with basic GRAPE algorithm
Ks, Lambda and Xi production at intermediate to high pT from Au+Au collisions at \sqrt{s_{NN}} = 39, 11.5 and 7.7 GeV
We report on the pT dependence of nuclear modification factors () for
Ks, Lambda, Xi and the Anti-Lambda/Ks ratios at mid-rapidity from Au+Au
collisions at \sqrt{s_{NN}} = 39, 11.5 and 7.7 GeV. At \sqrt{s_{NN}} = 39 GeV,
the data shows a baryon/meson separation at intermediate pT and a
suppression for Ks for pT up to 4.5 GeV/; the Anti-Lambda/Ks shows baryon
enhancement in the most central collisions. However, at \sqrt{s_{NN}} = 11.5
and 7.7 GeV, shows much less baryon/meson separation and
Anti-Lambda/Ks shows almost no baryon enhancement. These observations indicate
that the matter created in Au+Au collisions at \sqrt{s_{NN}} = 11.5 or 7.7 GeV
might be distinct from that created at \sqrt{s_{NN}} = 39 GeV.Comment: 4 pages, 2 figures, to appear in the proceedings of 7th International
Workshop on Critical Point and Onset of Deconfinement (CPOD2011), Wuhan,
China, Nov. 7-11, 201
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