11/25 Entanglement, non-unitary conformal field theories, and non-Hermitian quantum systems

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Time: 1:20pm~3:10pm, November 25 (Thursday)
Title: Entanglement, non-unitary conformal field theories, and non-Hermitian quantum systems

Speaker: Prof. Po-Yau Chang
(Department of Physics, National Tsing Hua University)
Place: Science Building III 1F SC157

Abstract:

Entanglement is a powerful tool to diagnose many-body quantum systems. The triumph examples are the critical systems where the low energy property can be described by conformal field theories (CFTs). The central charge which uniquely characterizes the CFT can be perfectly extracted from the entanglement entropy. However, the entanglement properties for non-unitary CFTs are not well understood. Moreover, the microscopic models of fermionic systems which can be described by non-unitary CFTs have not been explored. In this colloquium, I would like to demonstrate several non-Hermitian fermionic systems which can be described by non-unitary CFTs, and show their entanglement properties can be correctly obtained by our proposed generic entanglement entropy.

11/18 Simulate quantum transport by quench dynamics using matrix product state

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Time: 1:20pm~3:10pm, November 18 (Thursday)
Title: Simulate quantum transport by quench dynamics using matrix product state
Speaker: Prof. Chia-Min Chung
(Department of Physics, National Sun Yat-Sen University)
Google Meet Link: http://meet.google.com/xhy-yotv-wax

Abstract: Studying the transport properties of a nanostructure is a key tool in understanding and developing quantum devices. In this work we develop a method to simulate quantum transport in interacting systems using matrix product state. In particular we develop a method to simulate the current in a superconducting chain with charging energy, which is close related to a Majorana chain system. We benchmark our result in both a quantum dot system and a Majorana chain.