Fig. 4: The effect of the CCC on C(3) (left panel) and the NPA absorption matrix element M(N) (right panel).
From: Giant non-linear susceptibility of hydrogenic donors in silicon and germanium
The abscissa is the binding energy of the ground state (which is 31.5 meV at Ucc = 0), \(\bar \omega _{2p} = (\omega _{2p_0} + \omega _{2p_ \pm })/2 - \omega_g\) is the average transition frequency to the 2p levels, and likewise for \(\bar \omega _{3p}\). The binding energies of the Group V shallow donors are indicated in the left panel. The resonance and zero-crossing in the left panel, as well as the peaks in the 2p0 (3PA) and 2sA1 (4PA) matrix element on the right are due to the (2ω) resonance with the intermediate 1sE state
