Dynamical signatures of the one-dimensional deconfined quantum critical point  

作　　者：Ning Xi Rong Yu 西宁;俞榕(Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices,Renmin University of China,Beijing 100872,China)

机构地区：[1]Department of Physics and Beijing Key Laboratory of Opto-electronic Functional Materials and Micro-nano Devices,Renmin University of China,Beijing 100872,China

出　　处：《Chinese Physics B》2022年第5期73-82,共10页中国物理B（英文版）

基　　金：Project supported by the National Science Foundation of China(Grant No.12174441);the Fundamental Research Funds for the Central Universities,China;the Research Funds of Remnin University of China(Grant No.18XNLG24)。

摘　　要：We study the critical scaling and dynamical signatures of fractionalized excitations at two different deconfined quantum critical points(DQCPs)in an S=1/2 spin chain using the time evolution of infinite matrix product states.The scaling of the correlation functions and the dispersion of the conserved current correlations explicitly show the emergence of enhanced continuous symmetries at these DQCPs.The dynamical structure factors in several different channels reveal the development of deconfined fractionalized excitations at the DQCPs.Furthermore,we find an effective spin-charge separation at the DQCP between the ferromagnetic(FM)and valence bond solid(VBS)phases,and identify two continua associated with different types of fractionalized excitations at the DQCP between the X-direction and Z-direction FM phases.Our findings not only provide direct evidence for the DQCP in one dimension but also shed light on exploring the DQCP in higher dimensions.

关 键 词：one-dimensional antiferromagnetism spin frustration deconfined quantum critical point spin dynamics infinite time-evolving block decimation 

分 类 号：O469[理学—凝聚态物理]