korean english


Home > 게시판 > 세미나

Brookhaven National Laboratory의 Christopher Homes교수님을 초청하여 아래와 같이 세미나를 개최합니다.

학과 구성원 여러분의 많은 참석을 부탁 드립니다. 


아 래


제목: Optical properties of iron-based conductors and superconductors


연사: Prof. Christopher Homes (Condensed Matter Physics and Materials Science Dept., Brookhaven National Laboratory) 


일시: 2014. 4. 21(월) 오후 2:00 ~ 4:00


장소: 삼성학술정보관 7층 Creative learning room


초록: In the high-temperature cuprate superconductors, only a single band is observed at the Fermi level; as a result the optical conductivity may be modeled using a single free-carrier component.  In a simple metal the Drude model usually sufficient; however, electronic correlations and electron-boson coupling in the cuprates require a more generalized form in which the scattering rate and the effective mass are both frequency dependent [1].  The iron-based conductors and superconductors are multiband materials with several bands crossing the Fermi level, resulting in multiple hole and electron pockets at the center and corners of the Brillouin zone, respectively [2].  The presence of multiple bands requires, at a minimum, a “two-Drude” model in which the electron and hole pockets are treated as separate contributions [3]. In general, the two-Drude approach reveals: (i) a strong component associated with the hole pocket with a large scattering rate (nearly incoherent transport) that is essentially temperature independent; (ii) a weaker component associated with the electron pocket whose scattering rate has a strong temperature dependence.  Some recent results using this approach in the pnictide materials BaFe2As2 (TN~138 K) and Ba0.6K0.4Fe2As2 (Tc~38 K) [4] will be discussed, as well as some preliminary findings the iron-chalcogenide systems, Fe1+Te (TN~68 K) and FeTe0.55Se0.45 (Tc~14 K) [5].

*This work done in collaboration with Yaomin Dai, Qiang Li, Jinsheng Wen, Zhijun Xu, Genda Gu, Ricardo Lobo, and Ana Akrap; work supported by the US Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering under Contract No. DE-AC02-98CH10886.

[1] A. V. Puchkov, D. N. Basov, and T. Timusk, J. Phys.: Condens. Matter 8, 10049 (1996).
[2] S. Raghu et al., Phys. Rev. B 77, 220503(R) (2008).
[3] D. Wu et al., Phys. Rev. B 81, 100512 (2010).
[4] Y. M. Dai et al., Phys. Rev. Lett. 111, 117001 (2013).
[5] C. C. Homes et al., Phys. Rev. B 81, 180508(R) (2010).

번호 제목 날짜 조회 수
공지 <12/8(Thu.) 11:00am>노벨상 소개 강연 - 2016년 노벨 물리학상: 위상 응집 물리의 탄생 2016.11.28 1090883
278 <10/9> 금속 단결정 물성과 자성 반도체 연구 2009.10.06 78567
277 <3/16> Introduction to Experimental Nuclear Astrophysics 2007.03.15 78512
276 <11/21>Super B factory @ KEK 2008.11.19 78463
275 <4/17>고온초전도 2세대 선재 : 현황 및 전망 2009.05.06 78414
274 <11/5> Optical spectroscopic probe on the surface state in three dimensional topological insulators 2012.10.24 78394
» <4/21(월) 오후 2시> Optical properties of iron-based conductors and superconductors 2014.04.15 78326
272 <11/30> Spinning Black Holes: key to Gamma-ray Bur... 2007.11.26 78208
271 <4/20> Chern-Simons gauge theories and M2 brane CFTs 2009.04.09 78045
270 <9/10> Low temperature graphene synthesis 2010.08.30 78011
269 <10/23> Measuring Transfer Reactions with Radioactive Beams 2012.10.15 77996
268 <5/15>강상관 전자계의 열전변환 응용 2009.05.08 77879
267 <4/24> How to introduce the monopole in quantum mechanics? 2012.04.23 77856
266 <11/10>Mutifunctional Magnetic Oxides (다 기능성 자성 산화물) 2006.11.08 77803
265 <11/10>한국원전중성미자실험(RENO) 2006.11.08 77710
264 <12/12> lattice structure in holographic models 2012.12.12 77590
263 <9/7(금)> Kondo Effect in Chiral Orbital Bands 2012.08.31 77569
262 <9/15> 2006.09.07 77533
261 <10/5> 국제핵융합로 프로젝트 및 이와 관련된 초전도 연구 2007.10.01 77346
260 <12/17(Tue.)> Nuclear spectroscopy with low energy reaction thermal neutrons in ILL 2019.12.17 77339
259 <Nov.20(Wed.)>At the End of Space and Time: Imaging the Black Hole in M 87 2019.11.14 77310