161216 Electron transport in 3D topological insulators

“Electron transport in 3D topological insulators” Dr. SungJae Cho Department of Physics, KAIST Dec. 16 (Fri.), 15:00 PM E6-2. 1st fl. #1323 Abstract: The three dimensional topological insulator (3D TI) is a new class of materials having metallic surface states while the bulk is insulating. The surface states have gapless Dirac dispersions with novel properties such as momentum-spin locking. Moreover, coupling the surface states to an s-wave superconductor is predicted…

Continue reading »

161216 케인 양자컴퓨터 구현의 첫 걸음

“케인 양자컴퓨터 구현의 첫 걸음” Dr. SoonChil Lee Department of Physics, KAIST Dec. 16 (Fri.), 13:30 PM E6-2. 1st fl. #1323 Abstract: 양자컴퓨터가 처음 실험적으로 데모된 이후 양자컴퓨터가 될 수 있는 많은 양자계가 제안되고 실제로 개발되고 있다. 현재 가장 가능성이 높은 양자컴퓨터 시스템으로는 이온덫, 초전도소자, 반도체기반스핀 시스템을 꼽을 수 있다. 반도체기반 기반 스핀 시스템은 NV center, SET 등을 이용한 읽기 기술이 매우 발전했으나 상호작용 조절이 아직 미숙한 편이다. 케인 양자컴퓨터에서는…

Continue reading »

161104 Quantum information experiments using few electron spins in semiconductors

“Quantum information experiments using few electron spins in semiconductors” Dr. Dohun Kim Department of Physics and Astronomy, Seoul National University Nov. 04 (Fri), 15:00 PM E6-2. 1st fl. #1323 Abstract: Isolated electron and nuclear spins provide promising platforms for constructing quantum two level systems, or qubits in semiconductors. This talk will review two seemingly different but actually closely related research areas; 1. artificially fabricated gate defined semiconductor quantum dot based…

Continue reading »

161104 Exotic phenomena at oxide LaAlO3/SrTiO3 hetero-interface and their applications

“Exotic phenomena at oxide LaAlO3/SrTiO3 hetero-interface and their applications” Dr. Jonghyun Song Department of Physics, Chungnam National University Nov. 04 (Fri), 13:30 PM E6-2. 1st fl. #1323 Abstract: great attentions. Here we report the fabrication of spintronics devices based upon the interface ferromagnetism of LaAlO3/SrTiO3 (LAO/STO) heterostructures. The choice of the LAO/STO structure was inspired by its high-mobility two-dimensional electron gas and a number of experimental investigations revealing the spin…

Continue reading »

161028 Light, Camera, Electrons: lonisation Potentials of Solids

“Light, Camera, Electrons: lonisation Potentials of Solids” Prof. Aron Walsh Dept. of Materials, Imperial College London, UK 2016.10.28. 2PM E6-6, Lecture Room 118 The absolute energies of electrons in solids determine important chemical and physical processes; however, they are notoriously difficult to measure or calculate. I will present a brief history of the development of the topic over the past century, in particular, on the transition from phenomenological to first-principles…

Continue reading »

161018 Hybrid quantum systems with mechanical oscillators

“Hybrid quantum systems with mechanical oscillators” Dr. JunHo Suh Korea Research Institute of Standards and Science Oct. 18 (Tue.), 15:00 PM E6-2. 1st fl. #1323 Abstract: Quantum machines are actively pursued to harness quantum coherence and entanglement as new resources for information processing and precision sensing. Among those activities, hybrid quantum systems are recognized as a promising platform for building multi-functional quantum machines by connecting quantum states in different physical…

Continue reading »

161018 Visualization of oxygen vacancy in motion and the interplay with electronic conduction

“Visualization of oxygen vacancy in motion and the interplay with electronic conduction” Dr. Chan-Ho Yang, Department of Physics, KAIST Oct. 18 (Tue.), 1:30 PM, 1st fl. #1323(E6-2) Abstract: The multiferroic BiFeO3 (BFO) is an interesting playground to explore correlated electronic conduction. Here, we substitute divalent Ca ions into the parent BFO and apply an external electric field at elevated temperatures to spatially redistribute spontaneously created oxygen vacancies, thereby generating hole…

Continue reading »

160921 Entanglement probe of two-impurity Kondo physics

“Entanglement probe of two-impurity Kondo physics” Dr. Henrik Johannesson University of Gothenburg (Sweden) and Beijing Computational Science Research Center (China) Sep. 21 (Wed.), 4:00 PM E6-2. 2st fl. #2502 The two-impurity Kondo model has bearings on a number of topical problems, from heavy-fermion physics to spin-based quantum computing. In this talk I will review what is known about the model and also present a novel approach to its study, initiated…

Continue reading »

160902 Quantum Electrical Transport in Topological Insulator Nanowires

Quantum Electrical Transport in Topological Insulator Nanowires Sep. 02(Fri) 4:00 PM, E6-2(1st fl) #1323 Dr. Yong-Joo Doh, Department of Physics and Photon Science, GIST Abstract: Single-crystalline nanostructures of β-Ag2Se and Bi2Se3, three-dimensional(3D) topological insulators (TIs), were synthesized using the chemical vapor transport method. The topological surface states were verified by measuring electronic transport properties such as the weak antilocalization effect, Aharonov-Bohm oscillations, and Shubnikov-de Haas oscillations.[1,2] The band inversion in…

Continue reading »

160902 Nanoscale Thermal Physics: Seebeck Effect and Nanoscale Friction

“Nanoscale Thermal Physics: Seebeck Effect and Nanoscale Friction” Dr. Yong-Hyun Kim Graduate School of Nanoscience and Technology, KAIST Sep. 02 (Fri.), 14:30 PM E6-2. 1st fl. #1323 Abstract: Heat, a measure of entropy, is largely perceived to be diffusive and transported incoherently by charge carriers (electrons and holes) and lattice vibrations (phonons) in a material. Because heat can be carried by many different (quasi-)particles, it is generally hard to spatially…

Continue reading »