* PHYSICS/BK21 SEMINAR *

To conduct or not to conduct: zero temperature ground state of 2D electrons

연사: Jongsoo Yoon[University of Virginia]

일시: 2007 년 6 월 13 일 15:00

장소: 물리학과 세미나실(공학3동 201호)

ABSTRACT:

2D superconductors are expected to become an electrical insulator in the zero temperature limit when the superconductivity is suppressed by disorder or magnetic fields. However, superconducting tantalum thin films are found to exhibit superconductor-metal-insulator transition in the zero temperature limit tuned by magnetic fields. In strong contrast to the popular belief that the metallic phase is due to the electrons’ failure to cool, our recent experiments demonstrate that the metallic phase is genuine and arises from the vortex dynamics in the presence of disorder. Details of transport characteristics of each phase and their implications towards the phase diagram in the magnetic field-temperature-disorder plane will be discussed.

문의처: 이성익(054-279-2073, silee@postech.ac.kr)