Optical absorption from boron-containing quantum dot structures

Abstract

This work studies optical absorption in the zinc-blende boron-containing quantum dot (QD) structures. Eight structures are studied; two of them are the ternary BInP/GaP and BInP/BP. The others are BGaAsP/BP, BAlAsP/BAs, BInAsP/InP, BGaInAs/GaAs, BGaInP/BP, and BInAsP/GaP. The emission wavelengths of the structures cover a broad spectrum range from UV to near-infrared. The structures with BAs and BP barriers emit at 227,292nm. The structures BInAsP/InP and BGaInAs/GaAs have peak absorptions at 870nm and 920nm wavelengths, while ternary and quaternary structures with GaP barrier are at 720 and 1200nm. The structures with GaP barrier have importance in silicon device technology. The absorption peaks are arranged where the smallest energy difference between the transition subbands correspond to a higher absorption peak and are associated with a wide bandgap energy difference between the barrier and QD. For boron increment by 0.005 in the QD region, the peak absorption of BInP/GaP and BInP/BP in the TE mode have a wider red-shift (170 nm) in the peak wavelength. BGaAsP/BP has an absorption peak four orders higher than BAlAsP/BP. For of BInAsP/InP QD structure, the absorption spectrum is increased by more than four times under 0.0001-mole fraction increment of boron.