Abstract
| Original language | English |
|---|---|
| Article number | 110406 |
| Journal | Solar Energy Materials and Solar Cells |
| Volume | 208 |
| Number of pages | 7 |
| ISSN | 0927-0248 |
| DOIs | |
| Publication status | Published - 2020 |
Keywords
- Upconversion of sub-band gap photons
- High-efficient photovoltaics
- Photonic enhancement
- Topology optimization
Cite this
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Strongly enhanced upconversion in trivalent erbium ions by tailored gold nanostructures: Toward high-efficient silicon-based photovoltaics. / Christiansen, Jeppe; Vester-Petersen, Joakim; Roesgaard, Søren; Møller, Søren H.; Christiansen, Rasmus E.; Sigmund, Ole; Madsen, Søren Peder; Balling, Peter; Julsgaard, Brian .
In: Solar Energy Materials and Solar Cells, Vol. 208, 110406, 2020.Research output: Contribution to journal › Journal article › Research › peer-review
TY - JOUR
T1 - Strongly enhanced upconversion in trivalent erbium ions by tailored gold nanostructures: Toward high-efficient silicon-based photovoltaics
AU - Christiansen, Jeppe
AU - Vester-Petersen, Joakim
AU - Roesgaard, Søren
AU - Møller, Søren H.
AU - Christiansen, Rasmus E.
AU - Sigmund, Ole
AU - Madsen, Søren Peder
AU - Balling, Peter
AU - Julsgaard, Brian
PY - 2020
Y1 - 2020
N2 - Upconversion of sub-band-gap photons constitutes a promising way for improving the efficiency of silicon-based solar cells beyond the Shockley-Queisser limit. 1500 nm to 980 nm upconversion by trivalent erbium ions is well-suited for this purpose, but the small absorption cross section hinders real-world applications. We employ tailored gold nanostructures to vastly improve the upconversion efficiency in erbium-doped TiO thin films. The nanostructures are found using topology optimization and parameter optimization and fabricated by electron beam lithography. In qualitative agreement with a theoretical model, the samples show substantial electric-field enhancements inside the upconverting films for excitation at 1500 nm for both s- and p-polarization under a wide range of incidence angles and excitation intensities. An unprecedented upconversion enhancement of 913 ± 51 is observed at 1.7 W cm−2. We derive a semi-empirical expression for the photonically enhanced upconversion efficiency, valid for all excitation intensities. This allows us to determine the upconversion properties needed to achieve significant improvements in real-world solar-cell devices through photonic-enhanced upconversion.
AB - Upconversion of sub-band-gap photons constitutes a promising way for improving the efficiency of silicon-based solar cells beyond the Shockley-Queisser limit. 1500 nm to 980 nm upconversion by trivalent erbium ions is well-suited for this purpose, but the small absorption cross section hinders real-world applications. We employ tailored gold nanostructures to vastly improve the upconversion efficiency in erbium-doped TiO thin films. The nanostructures are found using topology optimization and parameter optimization and fabricated by electron beam lithography. In qualitative agreement with a theoretical model, the samples show substantial electric-field enhancements inside the upconverting films for excitation at 1500 nm for both s- and p-polarization under a wide range of incidence angles and excitation intensities. An unprecedented upconversion enhancement of 913 ± 51 is observed at 1.7 W cm−2. We derive a semi-empirical expression for the photonically enhanced upconversion efficiency, valid for all excitation intensities. This allows us to determine the upconversion properties needed to achieve significant improvements in real-world solar-cell devices through photonic-enhanced upconversion.
KW - Upconversion of sub-band gap photons
KW - High-efficient photovoltaics
KW - Photonic enhancement
KW - Topology optimization
U2 - 10.1016/j.solmat.2020.110406
DO - 10.1016/j.solmat.2020.110406
M3 - Journal article
VL - 208
JO - Solar Energy Materials & Solar Cells
JF - Solar Energy Materials & Solar Cells
SN - 0927-0248
M1 - 110406
ER -