Patent ID: 6055254
Filing Date: 2000-04-25
Classification: B82Y,H01S

Abstract:
A quantum cascade (QC) superlattice (SL) light emitter comprising:a core region including a QC active region which comprises a multiplicity of repeat units, each repeat unit including a unipolar radiative transition (RT) SL region and an injection/relaxation (I/R) region, each of said RT SL regions comprising a plurality of quantum well (QW) layers interleaved with a plurality of barrier layers, said QW layers having energy states characterized by upper and lower minibands, andelectrodes for applying an electric field to said emitter effective to cause said RT regions to generate light at an energy determined by upper and lower energy levels within said minibands, characterized in thatin at least a first subset of said QW layers, the internal electronic potential is pre-biased so that, despite the presence of said applied field in said SLs, an essentially flatband condition of both said upper and lower minibands exists.