korean english


Home > 게시판 > 세미나

일시: 9월 22일(목) 오전 10:30

장소: 학술정보관 2층 프리젠테이션룸

○ 연사: 임  준  원 박사님 (Max-Planck-Institute, Germany)

Title: Bulk-boundary correspondence from the inter-cellular Zak phase

○ Abstract: 

The Zak phase $\gamma$, the generalization of the Berry phase to Bloch wave functions in solids, is often used to characterize inversion-symmetric 1D topological insulators; however, since its value can depend on the choice of real-space origin and unit cell, only the difference between the Zak phase of two regions is believed to be relevant. Here, we show that one can extract an origin-independent part of $\gamma$, the so-called inter-cellular Zak phase $\gamma^{\mathrm{inter}}$, which can be used as a bulk quantity to predict the number of surface modes as follows: a neutral finite 1D tight-binding system has $n_s = \gamma^{\mathrm{inter}}/\pi$ (mod 2) number of in-gap surface modes below the Fermi level if there exists a commensurate bulk unit cell that respects inversion symmetry. We demonstrate this by first verifying that $\pm e\gamma^{\mathrm{inter}}/2\pi$ (mod $e$) is equal to the extra charge accumulation in the surface region for a general translationally invariant 1D insulator, while the remnant part of $\gamma$, the intra-cellular Zak phase $\gamma^{\mathrm{intra}}$, corresponds to the electronic part of the dipole moment of the bulk's unit cell. Second, we show that the extra charge accumulation can be related to the number of surface modes when the unit cell is inversion symmetric. This bulk-boundary correspondence using $\gamma^{\mathrm{inter}}$ reduces to the conventional one using $\gamma$ when the real-space origin is at the inversion center. Our work thereby clarifies the usage of $\gamma$ in the bulk-boundary correspondence. We study several tight binding models to quantitatively check the relation between the extra charge accumulation and the inter-cellular Zak phase as well as the bulk-boundary correspondence using the inter-cellular Zak phase.

번호 제목 날짜 조회 수
공지 <12/8(Thu.) 11:00am>노벨상 소개 강연 - 2016년 노벨 물리학상: 위상 응집 물리의 탄생 2016.11.28 1029987
236 <March.24(Thu) 14:00> A new boson and muon g-2 2016.03.17 62895
235 <3/11(Mon) 10:30 am ~ >Probing Dark Matter at LIGO and Beyond 2019.03.04 62951
234 <10/1(Tue.) Mini-Workshop on BSM Physics with Neutrino Detectors 2019.09.30 63252
233 <10/5> Gauge fields. Past, present, future. 2012.10.05 63429
232 <6/15(Fri.) ~ 16(Sat.)> Formation of first star and galaxy, Gravitational waves from Binary Mergers of Sub-Solar Mass Dark Black Holes 2018.06.12 63741
231 <7/15(Fri.) 14:00> Electronic quasiparticles in the quantum dimer model 2016.07.12 63771
230 <9/11(목)> The effects of dark matter elastic scattering on the cosmological signals 2014.09.01 63831
229 <March 8(Tue) 18:00> Unsolved puzzles of Gamma-Ray Bursts 2016.03.03 63947
228 <2/7> Exotic phases in pyrochlore iridates 2013.02.05 64043
227 <May.27(Fri.) 10:00> Towards Magnetic 2D Materials 2016.04.27 64100
226 <2/9(월) 오전 11시> 특별 초청세미나 개최 안내 file 2015.02.03 64177
225 <Dec.30(Wed) 16:30> Some basics about the thermoelectricity; the semi-classical Boltzmann transport approach 2015.12.24 64379
224 <March.18(Fri) 11:00> High Pressure Synthesis and Characterization of Non-Oxide Superconductors 2016.03.14 64431
223 <10/11(Tue.) 15:00>Analysis of Individual Terrestrial Gamma-ray Flashes 2016.10.10 64550
222 <6/9(화)> 세미나 개최 안내 2015.06.09 64854
221 <4/15(수)> 세미나 개최 안내 2015.04.09 64907
» <9/22(Thu.) 10:30> Bulk-boundary correspondence from the inter-cellular Zak phase 2016.08.29 65035
219 <3/22> 석학초청 특별강연 – Pyeongyang Advances Its Nuclear Program 2012.03.07 65173
218 <Jan.28(Thu.)>X-ray Absorption Spectroscopy Study of Amorphous Oxide Thin Films 2021.01.27 65347
217 <9/2(Mon) 15:00 ~ >Status of the KM3NeT Deep Sea Neutrino Telescope 2019.08.26 65436