Tensor Network Studies on Steady States of one-dimensional Infinite-size Dissipative Quantum Chain

碩士 === 國立臺灣大學 === 物理學研究所 === 104 === Using tensor netwrok to simulate quantum system has been rapidly developed recently. A well-developed tensor network algorithm called infinite time-evolving block decimation (iTEBD) allows us to find the ground state and detect the phase transitions of various qu...

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Bibliographic Details
Main Authors: TE I, 易德
Other Authors: Ying-Jer Kao
Format: Others
Language:en_US
Published: 2016
Online Access:http://ndltd.ncl.edu.tw/handle/51822585938654656016
Description
Summary:碩士 === 國立臺灣大學 === 物理學研究所 === 104 === Using tensor netwrok to simulate quantum system has been rapidly developed recently. A well-developed tensor network algorithm called infinite time-evolving block decimation (iTEBD) allows us to find the ground state and detect the phase transitions of various quantum systems with great accuracy. In this work, we show that using iTEBD we can also determine the nonequilibrium steady states of one-dimensional dissipative quantum lattices in the thermodynamic limit. Besides conventional iTEBD algorithm, we propose some improvements on this algorithm, including four-local gate evolving block operator and k-th root on evolving block operator. By this means, we make the iTEBD algorithm more suitable for simulating dissipative quantum system. The primary benefit of using iTEBD algorithm on dssipative quantum systems is allowing one to bypass the potentially high entanglement during the transient dynamis of real time evolution to the steady states. We provide a demonstration with the transversed dissipative quantum Ising chain. We validate our results using real time evolution and some numerical methods.