Title :
Light Trapping in Single Coaxial Nanowires for Photovoltaic Applications
Author :
Liu, W.F. ; Oh, J.I. ; Shen, W.Z.
Author_Institution :
Dept. of Phys., Shanghai Jiao Tong Univ., Shanghai, China
Abstract :
We report a strong enhancement of the light absorption in single coaxial nanowires (NWs) of Si core/dielectric shells. We have calculated the light absorption coefficient within the framework of the Lorenz-Mie light scattering theory and found out that it is greatly increased by effective light trapping in Si cores owing to dielectric shells, as compared to that in Si NWs. We show that the strong absorption of light stems mainly from off-resonance enhancement and also from resonance contribution. By optimally tuning the core radius, the shell thickness, and the shell refractive index, we have obtained ~102% increase of the photocurrent.
Keywords :
Mie scattering; nanowires; photovoltaic cells; refractive index; Lorenz-Mie light scattering theory; light trapping; off-resonance enhancement; photovoltaic applications; shell refractive index; single coaxial nanowires; Absorption; Charge carrier processes; Photoconductivity; Photovoltaic cells; Photovoltaic systems; Silicon; Fano effect; leaky-mode resonances (LMRs); light trapping; off-resonance; single coaxial nanowires;
Journal_Title :
Electron Device Letters, IEEE
DOI :
10.1109/LED.2010.2086428
