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Register a new userGeneralized thermalization in quenched free Fermionic models
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Added by
Shankaranarayanan S
Publication date
2018
fields
Physics
and research's language is
English
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We investigate generalized thermalization in an isolated free Fermionic chain evolving from an out of equilibrium initial state through a sudden quench. We consider the quench where a Fermionic chain is broken into two disjoint chains. We focus on the evolution of the local observables namely, occupation number, information sharing and out-of-time-order correlations after the quench and study the relaxation of the observable, leading to generalized Gibbs ensemble for the system in the thermodynamic limit. We obtain the light cone formed by the evolution of the observables along the Fermionic lattice chain due to the sudden quench which abides by the Lieb-Robinson bound in quantum systems. We also analytically study a simpler model which captures the essential features of the system. Our analysis strongly suggest that the internal interactions within the system do not remain of much importance once the quench is sufficiently strong.
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