Design and Fabrication of Distributed Bragg Reflector Capable of Reflecting at Two Distinct Wavelengths for Enhancing Silicon Solar Cell Efficiency by Upconversion

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Solar cells made of single band gap material suffer from two fundamental losses: (1) non-absorbed photons with energies below the band gap of the absorber, and (2) thermalization losses due to the absorption of photons with energies well-above the band gap of the absorber. These fundamental losses can be reduced by spectrum reshaping in which a high energy photon can be converted to two or multiple lower energy photons (i.e. down-conversion) and/or two or more low energy photons can be converted to a high energy photon (i.e. up-conversion). In this study, a distributed Bragg reflector is designed and fabricated to reflect the light originated from the fundamental and first excited states of erbium ions back into silicon solar cells. The reflector has a total of 5 amorphous silicon and silicon dioxide stacks, and capable of reflecting around 90% near a wavelength of 980 nm and above 95% near a wavelength of 1550 nm. The distributed Bragg reflector structure developed in this study provides a cost-effective approach to boost the efficiency of silicon solar cells.

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Photonics upconversionsolar cellsdistributed Bragg reflector

Erciyes University Journal Of The Institute Of Science an‎d Technology

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Erciyes University Journal Of The Institute Of Science an‎d Technology