摘要
用因式分解法求出了Ｌａｎｄａｕ体系（带电粒子在垂直于均匀磁场的平面内的运动）的四类升降算子。
Using the factorization method, four kinds of raising and lowering operators of the Landau system (a planer charged particle moving in a uniform magnetic field) are derived and the corresponding selection rules and conserved quantum numbers are discussed.
