logo

korean english

게시판

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 1079644
487 <5/15> Quantum Critical Superconductivity 2013.05.09 70899
486 <2/9(월) 오전 11시> 특별 초청세미나 개최 안내 file 2015.02.03 71067
485 <12/30> Correlation between Raman scattering and conductance in a molecular junction 2013.12.23 71131
484 <11/28> 별이 빛나는 밤에… 2012.11.22 71265
483 <10/5> Gauge fields. Past, present, future. 2012.10.05 71288
482 <10/24> Dung-hai Lee 교수와의 간담회 2012.10.23 71290
481 <6/11> 나노제조기술의 개요 및 응용 2010.06.07 71506
480 <9/7> On Dark Matter and its indirect detection with box-shaped gamma-rays 2012.09.05 71541
479 <6/4> Korea's challenges ahead for nuclear energy industry 2010.05.31 71605
478 2013학년도 1학기 콜로퀴움 일정 2013.02.19 71675
477 <March 8(Tue) 18:00> Unsolved puzzles of Gamma-Ray Bursts 2016.03.03 71722
476 <12/5> 과학용어와 의학용어에 숨겨진 이야기 2012.11.28 71759
475 <9/21> 금융공학과 금융산업 2007.09.17 71820
474 <5/30> Dark Energy 2012.05.23 71854
473 <10/11(Tue.) 15:00>Analysis of Individual Terrestrial Gamma-ray Flashes 2016.10.10 71935
472 <12/12> 자성체의 스커미온 동역학 2012.12.06 72017
471 <May.15(Wed.)> Three-body problems and three-body forces in Classic and Quantum Systems 2019.05.08 72188
470 <Nov.20(Wed.)>At the End of Space and Time: Imaging the Black Hole in M 87 2019.11.14 72307
469 <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 72581
468 <12/2(화)> Emergent Quantum Phenomena in SrTiO3 Heterostructures 2014.11.21 72802