Furthermore, the above device can be modified by varying {HEAD ~ the band gap} of {TAIL ~ the active layer} 204 with the same layer structure being used 
of
Furthermore , the above device can be modified by varying { HEAD ~ the band gap } of { TAIL ~ the active layer } 204 with the same layer structure being used
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH