visual
visual

세미나

  • HOME
  • >
  • 소식
  • >
  • 세미나
날짜 2016-09-02 14:30 
연사  
장소 E6-2(1st fl.), #1323 

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 연사 제목
공지 2025-02-24 16:00    2025년 봄학기 콜로키움 안내
공지 2025-02-27 16:00    2025년 봄 물리학과 특별세미나 (광학/응집물리 분야)
394 2019-04-19 16:00    Graphene and hBN heterostructures file
393 2019-04-23 16:00    From Mott physics to high-temperature superconductivity file
392 2019-04-26 16:00    Robust Quantum Metrology using Strongly Interacting Spin Ensembles and Quantum Convolutional Neural Network file
391 2019-05-01 16:00    Raman and x-ray scattering study on correlated electron systems: two case examples file
390 2019-05-02 16:00    Anomalous optical properties of halide perovskites file
389 2019-05-03 11:00    Exotic Magnetism file
388 2019-05-08 16:00    Imaging valley dependent electron transport in 2D semiconductors file
387 2019-05-09 16:00    Quantum Optical Sensing Using Single Photons And Single Photon Emission from Single Emitters file
386 2019-05-21 16:00    Classification of flat bands according to the band-crossing singularity of Bloch wave functions file
385 2019-05-24 16:00    Infrared spectroscopy study on metal-insulator transitions in layered perovskite iridates file
384 2019-05-30 16:00    Tuning the excitonic properties of semiconductors with light-matter interactions file
383 2019-05-31 11:00    Cavity QED with Spin Qubits file
382 2019-06-04 17:00    Stochastic nature of bacterial eradication using antibiotics file
381 2019-06-12 15:00    The relation between free and interacting fermionic SPT phases file
380 2019-06-17 10:30    Chiral Spintronics file
379 2019-06-24 11:00    Topological photonic anomalies file
378 2019-06-27 14:00    Gapless Kitaev Spin Liquid to Loop and String Gases file
377 2019-06-28 13:30    Magnetic domains and domain wall conduction in pyrochlore iridate thin films and heterostructures file
376 2019-06-28 14:00    1st Research-exchange meeting of computational material physics file
375 2019-07-03 15:00    Many-body quantum electrodynamis (QED) with atoms and photons: A new platform for quantum optics" file