title: Absorption and quasiguided mode analysis of organic solar cells with photonic crystal photoactive layers.
abstract: We analyze optical absorption enhancements and quasiguided mode properties of organic solar cells with highly ordered nanostructured photoactive layers comprised of the bulk heterojunction blend, poly-3-hexylthiophene/[6,6]-phenyl-C61-butyric acid methyl ester (P3HT:PCBM) and a low index of refraction conducting material (LICM). This photonic crystal geometry is capable of enhancing spectral absorption by approximately 17% in part due to the excitation of quasiguided modes near the band edge of P3HT:PCBM. A nanostructure thickness between 200 nm and 300 nm is determined to be optimal, while the LICM must have an index of refraction approximately 0.3 lower than P3HT:PCBM to produce absorption enhancements. Quasiguided modes that differ in lifetime by an order of magnitude are also identified and yield absorption that is concentrated in the P3HT:PCBM flash layer.
authors.affiliation: Physics and Astronomy Department, University of North Carolina Chapel Hill, Chapel Hill, NC 27599, USA.
authors.forename: John R
authors.initials: JR
authors.lastname: Tumbleston
authors.forename: Doo-Hyun
authors.initials: DH
authors.lastname: Ko
authors.forename: Edward T
authors.initials: ET
authors.lastname: Samulski
authors.forename: Rene
authors.initials: R
authors.lastname: Lopez
mesh_terms: D000042:Absorption; D017076:Computer-Aided Design; D003460:Crystallization / Q000379:methods*; D011211:Electric Power Supplies; D004867:Equipment Design; D019544:Equipment Failure Analysis; D009930:Organic Chemicals / Q000737:chemistry*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012993:Solar Energy
chemical_list: D009930:Organic Chemicals