Abstract The third-order nonlinear intersubband optical absorption coefficient within the con-duction band of semiconductor superlattices with complex bases have been calculated using the density matrix formalism including intrasubband and intersubband relaxation. The sub-band dipole moments zij(k) and zii(k) are first studied in superlattices with complex bases including a general coupled-well basis and a general step-well basis. The results show that zij(k) and zii(k) are complicated functions of and strongly depends on the well parameters. The intersubband transition optical absorption coefficient $\alpha$($\omega$, I) is further studied. The numerical illustrations are also given.
Received: 18 October 1993
Accepted manuscript online:
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