Scientific Activities
Seminars
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Seminar of Center for Theoretical Physics: | |
| Title | Topologically ordered zigzag graphene nanoribbons |
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| Speaker | Le Hoang Anh |
| Affiliation | IBS Center for Quantum Nanoscience, Seoul, South Korea |
| Date | Thursday, 16-10-2025 |
| Time | 10:00 AM |
| Location | Room 312A, 10 Dao Tan, Giang Vo, Ha Noi |
| Abstract | In this talk, I am going to give an overview of our recent studies on topological order of zigzag graphene nanoribbons (ZGNRs). At the initial stage, we demonstrated that the interplay between zigzag termination, electron-electron interaction and disorder results in e/2 fractional charges localized on two zigzag edges of the ribbon. Subsequently, we proved that ZGNRs belong to the class of topological order, a state of matter that goes beyond the conventional Landau symmetry breaking theory [1]. One key feature of such a state is to exhibit long-range entanglement and a universal entanglement entropy [2]. Our recent effort advances this line in two directions. One showed that two-leg electron ladders belong to the same class of topological order as ZGNRs [3]. The other one showed the emergent spacetime geometry from the entanglement of the fractional charges, where the edge-to-edge mutual information plays a role as geodesic distance in hyperbolic space, reminiscent of the AdS/CFT correspondence [4]. [1] S.-R. Eric Yang et al., Phys. Rev. Research 2, 033109 (2020) [2] H.-A. Le et al., J. Phys.: Condens. Matter 36, 265604 (2024) [3] S.-R. Eric Yang et al., Phys. Rev. B 111, 205144 (2025) [4] H.-A. Le et al., “Quantum entanglement of anyonic charges and emergent spacetime geometry” under review (2025) |
| Host person | Trần Minh Tiến |