1999年喀兴林先生在《高等量子力学》一书中首次提出角动量量子数l的升降算符,这个算符其实是一秩不可约张量算符的一个简单实现.当给定一个磁量子数m,降算符能给出最小量子数l的状态,进而得到全部球谐函数的最低态|0,0〉.而通过升降算符的恰当组合,作用在这个最低态上就可以生成任意球谐函数|lm〉.
Two vector operators aimed at shifting angular momentum quantum number l in spherical harmonics |lm〉,primarily proposed by X.L.Ka in 1999,are in fact first rank irreducible tensor operators.For a given magnetic quantum number m,specific state |lm〉 in spherical harmonics with the lowest angular momentum quantum number l is obtained and how to use this state to generate whole set of spherical harmonics is illustrated.