title: 4-Terminal Tandem Photovoltaic Cell Using Two Layers of PTB7:PC71BM for Optimal Light Absorption.
abstract: A 4-terminal architecture is proposed in which two thin active layers (<100 nm) of PTB7:PC71BM are deposited on a two-sided ITO covered glass substrate. By modeling the electric field distribution inside the multilayer structure and applying an inverse solving problem procedure, we designed an optimal device architecture tailored to extract the highest photocurrent possible. By adopting such a 4-terminal configuration, we numerically demonstrated that even when the two subcells use identical absorber materials, the performance of the 4-terminal device may overcome the performance of the best equivalent single-junction device. In an experimental implementation of such a 4-terminal device, we demonstrate the viability of the approach and find a very good match with the trend of the numerical predictions.
authors.affiliation: ICFO, The Institute of Photonic Sciences Mediterranean Technology Park Castelldefels (Barcelona) 08860, Spain.
authors.forename: Paola
authors.initials: P
authors.lastname: Mantilla-Perez
authors.affiliation: ICFO, The Institute of Photonic Sciences Mediterranean Technology Park Castelldefels (Barcelona) 08860, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Martinez-Otero
authors.affiliation: ICFO, The Institute of Photonic Sciences Mediterranean Technology Park Castelldefels (Barcelona) 08860, Spain.
authors.forename: Pablo
authors.initials: P
authors.lastname: Romero-Gomez
authors.affiliation: ICFO, The Institute of Photonic Sciences Mediterranean Technology Park Castelldefels (Barcelona) 08860, Spain.|Departament de Física i Enginyeria Nuclear, Universitat Politècnica de Catalunya , Terrasa 08222, Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Martorell
keywords: 4-terminal device; dielectric spacer; optical simulations; organics; photovoltaics