Large Integrated Absorption Enhancement in Plasmonic Solar Cells by Combining Metallic Gratings and Antireflection Coatings

• Published in: Nano letters Vol. 11; no. 6; pp. 2195 - 2201
• Main Authors: Munday, Jeremy N, Atwater, Harry A
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 08.06.2011
• Subjects: Applied sciences; Collective excitations (including excitons, polarons, plasmons and other charge-density excitations); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Electric Power Supplies; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronics; Energy; Exact sciences and technology; Metals - chemistry; Molecular electronics, nanoelectronics; Nanotechnology - instrumentation; Natural energy; Photovoltaic conversion; Physics; Porosity; Refractometry - instrumentation; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices; Solar cells. Photoelectrochemical cells; Solar Energy; Surface and interface electron states; Surface Properties; Temperature; Solar cells; grating; absorption enhancement; plasmonics; photovoltaics; Frequency dependence; Charge carrier generation; Illumination; Plasmons; Spatial resolution; Antireflection coatings; Photovoltaic cell
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/nl101875t

We describe an ultrathin solar cell architecture that combines the benefits of both plasmonic photovoltaics and traditional antireflection coatings. Spatially resolved electron generation rates are used to determine the total integrated current improvement under AM1.5G solar illumination, which can reach a factor of 1.8. The frequency-dependent absorption is found to strongly correlate with the occupation of optical modes within the structure, and the improved absorption is mainly attributed to improved coupling to guided modes rather than localized resonant modes.