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arXiv · 1006.5814

The geometric phase and the dynamics of quantum phase transition induced by a linear quench

B. Basu·P. Bandyopadhyay
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Abstract

We have analysed here the role of the geometric phase in dynamical mechanism of quantum phase transition in the transverse Ising model. We have investigated the system when it is driven at a fixed rate characterized by a quench time $\tau_q$ across the critical point from a paramagnetic to ferromagnetic phase. Our argument is based on the fact that the spin fluctuation occurring during the critical slowing down causes random fluctuation in the ground state geometric phase at the critical regime. The correlation function of the random geometric phase determines the excitation probability of the quasiparticles, which are excited during the transition from the inital paramagnetic to the ferromagnetic phase. This helps us to evaluate the number density of the kinks formed during the transition, which is found to scale as $\tau_q^{-\frac{1}{2}}$. In addition, we have also estimated the spin-spin correlation at criticality.

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B. Basu, P. Bandyopadhyay. 2010-06-30. The geometric phase and the dynamics of quantum phase transition induced by a linear quench. https://doi.org/10.1088/1751-8113/43/35/354023

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