題目：Fractional exclusion and braid statistics in low dimensions
報告人：葉飛 副教授（南方科技大學）
時  間：2017年3月30日(周四)下午2:00
地  點：北京理工大學中心教學樓610
 

摘要：
The statistics of identical particles plays a crucial role in their physical properties, which usually has two aspects: (i) the exchange statistics, which is reflected by the monodromy of the many body wavefunction; and (ii) the exclusion statistics, which is based upon state counting. In three dimensions, there exist only the Fermi and Bose statistics. The antisymmetric (for fermion) and symmetric (for boson) wavefunctions usually imply the Pauli's exclusion statistics and the BEC without exclusion statistics, respectively. In one or two dimensional systems, the braid (fractional exchange) statistics is allowed which interpolates between symmetric and antisymmetric wave functions. The exclusion statistics can also be extended to the fractional case, first proposed by F. D. M. Haldane more than two decades ago, which leads to an intermediate distribution function between the Bose-Einstein and Fermi-Dirac distribution functions. Although at the two ends of statistics, namely, bosons and fermions, the exclusion statistics can be derived from the exchange statistics, but in general the relation between the fractional exchange and exclusion statistics are not clear. In this talk, we present our recent study on the relation between the two fractional statistics in one and two dimensional systems using the Chern-Simons gauge theory and its dimensional reduction form, and show that in some special cases the fractional exchange statistics can induce fractional exclusion statistics.

簡歷：
葉飛，南方科技大學副教授。本科與博士畢業(yè)于上海交通大學物理系。博后畢業(yè)于清華大學高等研究中心。曾先后在清華高研、中國科學院大學擔任副研究員和副教授。現(xiàn)執(zhí)教于南方科技大學。研究領域集中在凝聚態(tài)理論，包括拓撲絕緣體、分數(shù)量子霍爾效應、高溫超導理論等。在Phys. Rev. Lett., Phys. Rev. B等國際一流期刊發(fā)表論文數(shù)篇。
聯(lián)系方式：物理學院辦公室 （68913163）
 

邀請人：楊帆 教授
網(wǎng)    址：http://physics.bit.edu.cn/