Quantum calculations for the photodetachment cross sections of H−H− located between two walls

We re-investigate the photodetachment cross sections of H−H− in a quantum well consisting of two parallel hard walls using a quantum approach. The formulas for the cross sections are explicitly derived and compared with those derived by using closed-orbit theory (G.C. Yang, et al., Physica B 404 (2009) 1576 [15]). The present quantum results confirm the staircase pattern of the cross sections obtained earlier when the polarization of photons is parallel to the normal direction of the walls. However, we find that when the polarization is perpendicular to the normal direction of the walls, oscillations in the cross sections in the present quantum calculations are still present in contrast to the predictions of closed-orbit theory. The differences in the two results are large enough to be observable.