Fieldhyphen;induced merging of electronhyphen;tohyphen;lighthyphen;hole (ehyphen;lh) and electronhyphen;tohyphen;heavyhyphen;hole (ehyphen;hh) excitonic absorption edges in tensilehyphen;strained quantum wells is demonstrated for the first time. Photocurrent spectra (77 K) of a GaAs0.92P0.08/Al0.37Ga0.63As multiplehyphen;quantumhyphen;well structure embedded in aphyphen;ihyphen;ndiode clearly show reduction and eventual elimination of a zerohyphen;bias sim;7 meV splitting between theehyphen;lh andehyphen;hh exciton peaks with increasing reverse bias. The unique lsquo;lsquo;lighthyphen;holehyphen;uprsquo;rsquo; valence subband configuration required for this fieldhyphen;induced merging is achieved through a combination of tensile strain and quantumhyphen;size effects in the sim;95 Aring; GaAs0.92P0.08/Al0.37Ga0.63As multiple quantum wells. The ability to control and eliminate the splitting between theehyphen;lh andehyphen;hh absorption edges via an applied electric field offers possibilities for improving the performance of electroabsorption modulators.
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