The effective band gap of a GaAs/AlAs quantum well is given by E = Eg + E + Eh, where Eg is the band gap of GaAs at room temperature (1.39 eV) and E and Ef are the ground state energies in the conduction and valence band quantum wells. Use a simple infinite barrier approximation, and assume that the effective masses are me 0.067me and m 0.4me. = = (a) Calculate the quantum well width in which the effective band gap is 1.6 eV. (b) If the size of the well width has an uncertainty comparable with a monolayer thickness (0.286 nm), what is the resulting uncer- tainty in the wavelength of band-edge emission from this quan- tum well? Conduction band. Eg E Eg = 1.39 eV El Valence band