logo

korean english

게시판

Home > 게시판 > 세미나

동경대학교의 Matsumoto 박사님초청하여 아래와 같이 세미나를 개최합니다.


학과 구성원 여러분의 많은 참석을 부탁 드립니다


                        


     1. 일시: 2015 4 21(화) 오전 11

     2. 장소: 삼성학술정보관 7층 Creative Learning Room

     3. 초청연사: Dr. Yosuke Matsumoto (Institute for Solid State Physics, University of Tokyo, Japan)

     4. 제목: Novel quantum criticality beyond Doniach phase diagram

     5. Abstract: Novel quantum phases formed in the vicinity of a quantum critical point (QCP) is one of the most important topics for strongly correlated electron systems. So far, quantum criticality (QC) in heavy fermion systems has been studied mainly for Kondo lattice systems with integer valence. In this case, QC is usually related to magnetism and is understood by so called Doniach phase diagram. Here, we would like to discuss two examples of novel QC which are beyond this picture. The one is the novel QC found in the mixed valent YbAlB4 systems. The first Yb-based heavy fermion superconductor -YbAlB4 [1,2] exhibits QC without tuning any control parameter, indicating formation of a strange metal phase [3]. Recent resistivity measurements under pressure have revealed indeed that a non-Fermi liquid phase extends over a finite pressure range up to ~ 0.4 GPa [4]. We will further discuss a sharp valence crossover induced by a chemical substitution in -YbAlB4, which is an isostructural polymorph of -YbAlB4. Interestingly, we observed a pronounced NFL behavior as a possible evidence of a quantum valence criticality [5]. Another example is a possibility of quantum criticality arising from orbital degrees of freedom. Our recent studies revealed that PrT2Al20 (T = Ti, V) are ideal systems to study such possibilities. The both systems have the nonmagnetic cubic 3 crystal electric field doublet [6]. In addition, the hybridization is strong as is evident in many physical properties [6]. We would like to discuss heavy fermion superconductivity observed inside the multipole ordering phases [7-9].


Reference
[1] S. Nakatsuji et al., Nature Phys. 4, 603 (2008).
[2] K. Kuga et al., Phys. Rev. Lett. 101, 137004 (2008).
[3] Y. Matsumoto et al., Science 331, 316 (2011). References therein.
[4] T. Tomita, K. Kuga, Y. Uwatoko, P. Coleman, and S. Nakatsuji, preprint (2015).
[5] K. Kuga et al., preprint (2015).
[6] A. Sakai, and S. Nakatsuji, JPSJ 80, 063701 (2011). References therein.
[7] A. Sakai et al., JPSJ 81, 083702 (2012).
[8] K. Matsubayashi et al., PRL 109, 187004 (2012).
[9] M. Tsujimoto et al., PRL 113, 267001 (2014). References therein.

번호 제목 날짜 조회 수
공지 <12/8(Thu.) 11:00am>노벨상 소개 강연 - 2016년 노벨 물리학상: 위상 응집 물리의 탄생 2016.11.28 1079590
287 <11/19> From Schrödinger's cat to quantum technology using light 2010.11.11 99276
286 <11/12> 다윈의 식탁 - 현대 진화론의 맛있는 논쟁 2010.11.05 82815
285 <11/5> Modified nucleic acid systems for biomedical applications 2010.11.01 127033
284 <10/29> 분자 나노자성체에 대한 소개 2010.10.15 81068
283 <10/15> Electric control of magnetic nanostructures via spin torque 2010.10.08 115781
282 <10/8>"Einstein was wrong?"--Two-proton spin- correlation measurement for EPR paradox. 2010.10.04 149342
281 <9/17>Computational studies of materials and nanostructures 2010.09.08 80781
280 <9/10> Low temperature graphene synthesis 2010.08.30 77529
279 2010학년도 2학기 콜로퀴엄 일정 안내 2010.08.10 81627
278 <6/11> 나노제조기술의 개요 및 응용 2010.06.07 71505
277 <6/4> Korea's challenges ahead for nuclear energy industry 2010.05.31 71601
276 <5/14> Search for exotic materials: strongly correlated electron system 2010.05.10 116882
275 <4/30> Characterization of Molecular Transistors and Organic Memory Devices 2010.04.15 89681
274 <4/16>같은 곳을 바라보는 다른 시선 2010.04.09 90145
273 <4/9> 중이온가속기 KoRIA 구축 계획 2010.04.02 93174
272 <4/2> 다중벽탄소나노튜브를 이용한 AFM 탐침 개발과 응용 2010.03.29 80889
271 <3/26> Fractional Hall Physics of Epitaxial Graphene: 2010.03.19 121579
270 <3/19> Bioconjugates of nanomaterials for biochip & biosensor applications 2010.03.16 125887
269 <3/12> Nano Structure of wide Band Gap Semiconductors 2010.03.08 93905
268 <12/4> The "Physics" of Climate Change 2009.12.02 119193