title: Deliberate Switching of Single Photochromic Triads.
abstract: Photochromic molecules can be reversibly converted between two bistable conformations by light, and are considered as promising building blocks in novel macromolecular structures for sensing and imaging techniques. We have studied individual molecular triads consisting of two strong fluorophores (perylene bisimide) that are covalently linked via a photochromic unit (dithienylcyclopentene) and distinguished between deliberate switching and spontaneous blinking. It was verified that the probability for observing deliberate light-induced switching of a single triad (rather than stochastic blinking) amounts to 0.8 ± 0.1. In a few exceptional cases this probability can exceed 0.95. These numbers are sufficiently large for application in sensitive biosensing, and super-resolution imaging. This opens the possibility to develop devices that can be controlled by an external optical stimulus on a truly molecular length scale.
authors.affiliation: Experimental Physics IV, University of Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Maier
authors.affiliation: Experimental Physics IV, University of Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Martti
authors.initials: M
authors.lastname: Pärs
authors.affiliation: Applied Functional Polymers, University of Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Tina
authors.initials: T
authors.lastname: Weller
authors.affiliation: Applied Functional Polymers, University of Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Mukundan
authors.initials: M
authors.lastname: Thelakkat
authors.affiliation: Experimental Physics IV, University of Bayreuth, 95440 Bayreuth, Germany.
authors.forename: Jürgen
authors.initials: J
authors.lastname: Köhler