title: Nonlinear optical response of photochromic azobenzene-functionalized self-assembled monolayers.
abstract: The combination of photochromic and nonlinear optical (NLO) properties of azobenzene-functionalized self-assembled monolayers (SAMs) constitutes an intriguing step towards novel photonic and optoelectronic devices. By utilizing the second-order NLO process of second harmonic generation (SHG), supported by density-functional theory and correlated wave function method calculations, we demonstrate that the photochromic interface provides the necessary prerequisites en route towards possible future technical applications: we find a high NLO contrast on the order of 16% between the switching states. These are furthermore accessible reversibly and with high efficiencies in terms of cross sections on the order of 10(-18) cm(2) for both photoisomerization reactions, i.e., drivable by means of low-power LED light sources. Finally, both photostationary states (PSSs) are thermally stable at ambient conditions.
authors.affiliation: Physikalisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, 69120 Heildeberg, Germany. tegeder@uni-heidelberg.de.
authors.forename: Michael
authors.initials: M
authors.lastname: Schulze
authors.forename: Manuel
authors.initials: M
authors.lastname: Utecht
authors.forename: Thomas
authors.initials: T
authors.lastname: Moldt
authors.forename: Daniel
authors.initials: D
authors.lastname: Przyrembel
authors.forename: Cornelius
authors.initials: C
authors.lastname: Gahl
authors.forename: Martin
authors.initials: M
authors.lastname: Weinelt
authors.forename: Peter
authors.initials: P
authors.lastname: Saalfrank
authors.forename: Petra
authors.initials: P
authors.lastname: Tegeder