depth is established by setting band offsets two bands used to determine the quantum well depth are the valence and conduction bands the valence band associated with hole wells and the conduction band with electron wells setting of the bands determines the offsets mev mili electron volts for the quantum well and provides depth associated with the confinement of holes and electrons fig1 22 provide graphical illustrations of vcsel behavior at different well depths although the simulations illustrated in fig1 22 were conducted on algaas quantum wells the overall analysis is applicable to other materials since temperature will generally be the same and effective masses are not vastly different between devices fig1 16 are a first group of graphs representing the analysis of a normal set of three quantum wells 1401 for an 850 nm vcsel under bias actively lasing in this case there is substantial p doping which suppresses the electron concentration relative to the hole concentration as shown on the vertical axis of the graph in fig1 well depth of three quantum wells 1401 was established by setting the valence band offsets 1405 at approximately 125 mev and the conduction band offset 1410 at 250 mev it should be appreciated that the quantum well number does not have to.