Our work demonstrates nonadiabatic tunneling of photoelectrons in the near-field of gold nanostructures, which occurs in the transition region between the multi-photon-induced photoemission and tunneling emission regimes. Measured kinetic energy spectra at higher laser intensities indicates strong-field electron accelaration and recollision, characteristic for the tunneling emission regime. At the same time, constant scaling of the photoelectron current with the intensity has been measured, a trait of the multi-photon-induced photoemission regime. The Keldysh value of γ ≈ 2 for the transition was determined by analyzing the measured photoemission spectra. This value is in good agreement with the results acquired by the numerical solution of the Time-Dependent Schrödinger Equation.
The color of a crystalline silicon (c-Si) solar cell is mainly determined by its anti-reflective coating. This is a lambda/4 coating made from a transparent dielectric material. The thickness of the anti-reflective coating is optimized for maximal photocurrent generation, resulting in the typical blue or black colors of c-Si solar cells. However, for building-integrated photovoltaic (BiPV) applications the color of the solar cells is demanded to be tunable – ideally by a cheap and flexible coating process on standard (low cost) c-Si solar cells. Such a coating can be realized by applying plasmonic coloring which is a rapidly growing technology for high-quality color filtering and rendering for different fields of application (displays, imaging,…).
In this contribution, we present results of an approach for tuning the color of standard industrial c-Si solar cells that is based on coating them with metallic nano-particles. In particular, thin films (< 20 nm) of a metal (e.g., silver) were sputtered onto c-Si solar cells and thermally annealed subsequently. The sizes and the shapes of the nano-particles (characterized by SEM) were found to depend on the thickness of the deposited films and the surface roughness of the substrates/solar cells. With such an approach it is possible to tune the color of the standard c-Si cells from blue to green and brownish/red. The position of the resonance peak in the reflection spectrum was found to be almost independent from the angle of incidence. This low angular sensitivity is a clear advantage compared to alternative color tuning methods, for which additional dielectric thin films are deposited on c-Si solar cells.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.