Hoạt động khoa học
Seminar
Seminar Trung tâm Vật lý lý thuyết: | |
Tên báo cáo | Reflection symmetric second-order topological insulators and superconductors |
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Người trình bày | Dr. Luka Trifunovic |
Cơ quan | Freie Universitaet, Berlin |
Ngày | Thứ Sáu, 11-08-2017 |
Giờ | 09:30 AM |
Địa điểm | Phòng 202 (Thư viện), Viện Vật lý, 10 Đào Tấn, Ba Đình, Hà Nội |
Tóm tắt | Second-order topological insulators are crystalline insulators with a gapped bulk and gapped crystalline boundaries, but topologically protected gapless states at the intersection of two boundaries. Without further spatial symmetries, five of the ten Altland-Zirnbauer symmetry classes allow for the existence of such second-order topological insulators in two and three dimensions. We show that reflection symmetry can be employed to systematically generate examples of second-order topological insulators and superconductors, although the topologically protected states at corners (in two dimensions) or at crystal edges (in three dimensions) continue to exist if reflection symmetry is broken. A three-dimensional second-order topological insulator with broken time-reversal symmetry shows a Hall conductance quantized in units of e^2/h. |
Người chủ trì | Nguyễn Thị Kim Thanh |