visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2016-09-02 14:30 
일시 Sep. 02(Fri) 2:30 PM 
장소 E6-2(1st fl.), #1323 
연사 Dr. Yong-Hyun Kim,Graduate School of Nanoscience and Technology, KAIST 

Nanoscale Thermal Physics: Seebeck Effect and Nanoscale Friction

 

Sep. 02(Fri) 2:30 PM, E6-2(1st fl.), #1323
Dr. Yong-Hyun Kim,Graduate School of Nanoscience and Technology, KAIST

 

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 localize the transport of the thermal energy. Heat transport is thus considered to be a challenging means of the local probing of a material and of its electronic states. Recently, we have shown that coherent electron and heat transport through a point-like contact in the atomic force microscope set-up at the ultra-high vacuum condition produces an atomic Seebeck effect, which represents the novel imaging principle of surface wave functions with atomic resolution. The heat-based scanning Seebeck microscopy clearly contrasts to the vacuum tunneling-based scanning tunneling microscopy, a hitherto golden standard of imaging surface wave functions. We have found that the coherent transmission probabilities of electron and phonon across the tip-sample junction are equally important for the imaging capability of the scanning Seebeck microscope. Very recently, we have reported that abnormally enhanced nanoscale friction on ice-trapped graphene surface could be understood in terms of flexural phonon couplings between graphene and substrate (e.g. mica). Also, we have found that energetic tunneling electrons in scanning tunneling microscopy can cause chemical reactions at the single molecule level by locally exciting phonon modes of molecules (or nanoscale heating) under the tip through the inelastic electron-phonon scattering. In this talk, I will discuss how we theoretically explore nanoscale thermal physics including thermoelectric imaging, nanoscale friction, and single molecule chemical reaction, specifically in the setup of scanning probe microscopy.


Contact: Sung Jae Cho, Physics Dept., (sungjae.cho@kaist.ac.kr)

번호 날짜 장소 제목
420 2019-03-26 15:00  E6-2. 2st fl. #2501  Consideration of thermal Hall effect in frustrated and un-frustrated quantum magnets file
419 2019-01-07 15:00  E6-2. 2st fl. #2501  Many-Body Invariants for Multipoles in Higher-Order Topological Insulators file
418 2018-06-18 10:00  E6-2. 2nd fl. #2502  Rydberg electromagnetically induced transparency and microwave-to-optical conversion using Rydberg atoms file
417 2019-01-09 16:00  E6-2. 2nd fl. #2501  Molecular Mott state in the deficient spinel GaV4S8 file
416 2015-10-16 16:00  E6-2. 2nd fl. #2501  Fluctuations of entropy production in partially masked electric circuits
415 2015-09-14 14:00  E6-2. 2nd fl. #2501  Ultrafast X-ray Studies on Dynamics Matter in Extreme Conditions
414 2016-04-01 14:30  E6-2. 1st fl. #1501  Interference of single charged particles without a loop and dynamic nonlocality
413 2016-04-01 16:15  E6-2. 1st fl. #1501  Cotunneling drag effect in Coulomb-coupled quantum dots
412 2016-03-11 16:00  E6-2. 1st fl. #1501  Jan. Switching handedness of of chiral solitons in Z4 topological insulators
411 2016-04-08 13:30  E6-2. 1st fl. #1501  Theoretical Overview of Iron-based superconductors and its future
410 2016-03-11 13:30  E6-2. 1st fl. #1501  Topological phases of matter in nonequilibrium: Topology of the Wannier-Stark ladder
409 2022-05-25 16:00  E6-2. 1st fl. #1323 / Zoom  Uncovering New Lampposts for Dark Matter: Continuum or Conformal
408 2022-09-30 14:30  E6-2. 1st fl. #1323 & Zoom  Putting a spin on the Josephson effect file
407 2022-11-18 14:30  E6-2. 1st fl. #1323 & Zoom  Kondo cloud condensation in a highly-doped semiconductor metal file
406 2022-09-30 16:00  E6-2. 1st fl. #1323 & Zoom  Spin-orbit torque-based spintronic devices file
405 2022-11-18 16:00  E6-2. 1st fl. #1323 & Zoom  Qubits, new experimental tools for physics file
404 2022-11-09 16:00  E6-2. 1st fl. #1323  Radio Astronomy, Radio Interferometry, and Multi-wavelength Studies on Relativistic Jets
403 2022-11-10 16:00  E6-2. 1st fl. #1323  Probing the Origin of Cosmic Infrared Background and Future Prospects with SPHEREx
402 2022-06-10 16:00  E6-2. 1st fl. #1323  Fe5GeTe2의 나선형 자성특성과 자기저항의 전류밀도 의존성 연구 file
401 2022-06-10 14:30  E6-2. 1st fl. #1323  Combinatorial strategy for condensed matter physics: study on rare earth hexaborides thin films file