III-V semiconductors are extensively investigated for fabrication of quantum well infrared photodetectors (QWIPs); however the operation wavelength is limited by the bandoffset of the materials allowing infrared transitions for wavelength larger than 3.1 um. For wavelength shorter than 1.7 um band to band transitions are easily employed. Thus, in III-V QWIPs, the range between 1.7 and 3.1 um cannot be reached either by band-to-band or by intraband transitions. In this thesis a specially designed superlattice structure is proposed in order to detect radiation within this forbidden range. The structure proposed consists of a superlattice with a wider central quantum well, which generates a modulation in the continuum creating minibands and minigaps for energies above the bottom of the conduction band of the quantum well, including in the continuum. With this approach the limitation of having bound states only with energies below the barrier no longer holds and it is possible to detect energies higher than the limit imposed by the bandoffset of the materials. Theoretical simulations for the structure were performed and absorption, dark current, and photocurrent measurements were carried out showing peaks at 2.1 um, in close agreement with the theoretically expected value.