具有一般邊界條件的Non-Hermitian SSH模型

Non-Hermitian SSH Model with General Boundary Condition

黃正源(Huang Cheng-Yuan)

指導教授 ： 高賢忠

國立臺灣師範大學/理學院/物理學系/碩士(2023年)

https://doi.org/10.6345/NTNU202300045

摘要

本文主要研究滿足一般邊界條界的Non-Hermitian Su-Schrieffer-Heeger (nSSH)模型。我首先介紹Su-Schrieffer-Heeger (SSH)模型，透過bulk edge correspondence來預測該系統邊界態的數目。接著將這些想法推廣至non-Hermitian的系統，並且介紹更一般的邊界條件。我發現不同於SSH模型，此時系統存在skin effect及exceptional points。並且列出exceptional points出現的條件，討論其中有趣的性質。

關鍵字

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並列摘要

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並列關鍵字

SSH model ； bulk edge correspondencce ； non-Hermitian SSH model ； exceptional points

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