报告题目: |
Quantum criticality of semimetal-insulator transitions |
报告人: |
Bohm-Jung Yang |
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Department of Physics and Astronomy, Seoul National University
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报告时间: |
2016-12-21 16:00 |
报告地点: |
Conference Hall 322, Science Building, Tsinghua University |
主办单位: |
高等研究院 |
简介: |
In this talk, I am going to talk about the quantum criticality of a semi-metal insulator transition in interacting electronic systems in both 2D and 3D.At the quantum critical point, the low energy excitations can be described byWeyl fermions with anisotropic dispersion which is quadratic along one direction but linear along the other orthogonal directions.The interplay between the anisotropic dispersion and the Coulomb interactionbrings about a new screening phenomenon distinct fromthe conventional Thomas-Fermi screening in metals and logarithmic screening in Dirac fermions. Such an unusual form of the screened Coulomb interaction makes the fermionic quasiparticle to show almost free particle-like behavior in 3D. Whereas in 2D, the anisotropic momentum dependence of screened Coulomb interaction gives rise to marginal Fermi liquid behavior of quasi-particles. |
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