Binding Energy of a Screened Hydrogenic Impurity in a Quasi One-Dimensional Electron Gas

抄録

We report the calculation of the binding energy E_B of a screened hydrogen impurity placed at center of quantum well wire with a square cross-section of the length L, which is surrounded by an infinite barrier. The random-phase-approximation static dielectric function at zero temperature and electric quantum limit are adopted. For the case that L is comparable to a_B (a_B is the effective Bohr radius of hydrogenic impurity in bulk), it is shown that E_B is minimum near a_Bk_F=0.5 (k_F is the Fermi wave number) and the screening effect of mobile carriers on E_B is neglected for the case a_Bk_F>>1.