Pattern formation under bistable electro-optical absorption in quantum wells: II

In the first part of this work (Bonilla L L, Kochelap V A and Velasco C A 1 999 J. Phys.: Condens. Matter 11 6395) we formulated and analysed a model o f transverse self-sustained pattern formation in a photoexcited and voltage -biased quantum well(QW) structure. Our model explained the formation of pa tterns of quasi-neutral two-dimensional electron-hole plasma whose intrinsi c bistability was shown in recent experiments. We found patterns containing regions with different spreading of the electron and hole wave functions a nd different densities of the two-dimensional electron-hole plasma. In this second part we extend our results to QWs with finite transverse dim ension. We will show that the boundary conditions at the edges of the QW la yer control the behaviour of the patterns. We will study the stability of t he patterns and will show its strong dependence on the boundary conditions. A linear stability criterion for these patterns is presented and compared with numerical simulations.