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arXiv · 0706.2480

Operator space entanglement entropy in transverse Ising chain

Tomaz Prosen·Iztok Pizorn
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Abstract

The efficiency of time dependent density matrix renormalization group methods is intrinsically connected with the rate of entanglement growth. We introduce a new measure of entanglement in the space of operators and show, for transverse Ising spin 1/2 chain, that the simulation of observables, contrary to simulation of typical pure quantum states, is efficient for initial local operators. For initial operators with a finite index in Majorana representation, the operator space entanglement entropy saturates with time to a level which is calculated analytically, while for initial operators with infinite index the growth of operator space entanglement entropy is shown to be logarithmic.

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Tomaz Prosen, Iztok Pizorn. 2007-08-06. Operator space entanglement entropy in transverse Ising chain. https://doi.org/10.1103/physreva.76.032316

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