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تسجيل مستخدم جديدTheory of defect production in nonlinear quench across a quantum critical point
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We study defect production in a quantum system subjected to a nonlinear power law quench which takes it either through a quantum critical or multicritical point or along a quantum critical line. We elaborate on our earlier work [D. Sen, K. Sengupta, S. Mondal, prl 101, 016806 (2008)] and present a detailed analysis of the scaling of the defect density $n$ with the quench rate $tau$ and exponent $al$ for each of the above-mentioned cases. We also compute the correlation functions for defects generated in nonlinear quenches through a quantum critical point and discuss the dependence of the amplitudes of such correlation functions on the exponent $al$. We discuss several experimental systems where these theoretical predictions can be tested.
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