위상양자물성 연구실에서 National High Magnetic Field Laboratory의 이경민 박사님을 초청하여 아래와 같이 세미나를 개최합니다.

학과 구성원 여러분의 많은 참석을 부탁 드립니다.

온-오프 혼합으로 진행되는 세미나입니다.

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○ Title: Frustration-induced Athermal Behaviors: Hilbert Space Fragmentation and Quantum Many-Body Scars

○ Speaker: 이  경  민  박사님 (National High Magnetic Field Laboratory)

○ Date/time: 2021. 6. 1 (Tue.) 16:30

○ 온라인 참여방법: https://meet64.webex.com/meet/pr1829909900
   

○ Place: Natural Science 1,  Room No. 31317

○ Abstract: Although most interacting quantum systems thermalize locally on short time scales independent of initial conditions, recent developments have shown that this is not always the case: Athermal behaviors have been observed in disordered systems, and more recently, evidence for athermal eigenstates, known as quantum many-body scars, has emerged in disorder-free models with constrained dynamics. In this talk, I will demonstrate that geometric frustration provides a pathway to athermal behaviors without disorder. In a clean system, local constraints can lead to a fragmented Hilbert space where certain initial states fail to reach the thermal steady state. Such fragmentation naturally arises in many frustrated systems with low-energy “ice manifolds” which gives rise to a broad range of relaxation times for different initial states. Focusing on the highly frustrated kagome lattice, I will discuss the phenomenology of fragmentation in two spin-1/2 Hamiltonians with simple two-body interactions: the Balents-Fisher-Girvin model (easy-axis regime), and the three-coloring model (easy-plane regime), both with constrained Hilbert spaces. Furthermore, I will discuss the existence of quantum many-body scar eigenstates in modified three-coloring models with robust quantum revivals, which can be generalized to other lattices.