分裂的电子

Electronic fractionalization

电子是组成世界万物的一种基本粒子.其电荷及自旋自由度在电子处于游离状态时牢不可分.但在某些低维强关联体系中,电子与其他粒子的相互作用会导致两种不同准粒子的出现.其中一种具有非零的正电荷,但自旋自由度为零,称为空穴子.另外一种准粒子具有正好相反的性质,即其电荷为零,然而自旋等于电子的自旋,被称为自旋子.这种现象被形象地称为电子的电荷-自旋分离,并被用来解释高温超导电性.最近,空穴子和自旋子的存在进一步得到了实验的证实.此外实验中还观察到另外一种准粒子,它只携带了电子绕核运动的属性,被称为轨道子.在本文中,我们将结合实验,对于这些有趣的现象做一介绍.

The electron is a fundamental building block of nature. Its charge and spin degrees of freedom are indivisible in isolation. However,in some low- dimensional strongly correlated electronic systems,the interaction between electrons and other particles will lead to the emergence of two different quasiparticles. One of the new particles created,the spinon,carries positive charge and no spin,and the other,the spinon,carries the electron＇s spin. Such phenomenon is called spin- charge separation and adopted to explain high- temperature superconductivity. Recently,the existence of holon and spinon was verified in experiments. Also,an orbiton carrying the property,which arises from the electron＇s motion around the nucleus,was observed. In this article,combined with the progress in experiments,we describe these interesting phenomena.