title: Signal enhancement in cantilever magnetometry based on a co-resonantly coupled sensor.
abstract: Cantilever magnetometry is a measurement technique used to study magnetic nanoparticles. With decreasing sample size, the signal strength is significantly reduced, requiring advances of the technique. Ultrathin and slender cantilevers can address this challenge but lead to increased complexity of detection. We present an approach based on the co-resonant coupling of a micro- and a nanometer-sized cantilever. Via matching of the resonance frequencies of the two subsystems we induce a strong interplay between the oscillations of the two cantilevers, allowing for a detection of interactions between the sensitive nanocantilever and external influences in the amplitude response curve of the microcantilever. In our magnetometry experiment we used an iron-filled carbon nanotube acting simultaneously as nanocantilever and magnetic sample. Measurements revealed an enhancement of the commonly used frequency shift signal by five orders of magnitude compared to conventional cantilever magnetometry experiments with similar nanomagnets. With this experiment we do not only demonstrate the functionality of our sensor design but also its potential for very sensitive magnetometry measurements while maintaining a facile oscillation detection with a conventional microcantilever setup.
authors.affiliation: Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany.
authors.forename: Julia
authors.initials: J
authors.lastname: Körner
authors.affiliation: Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany.
authors.forename: Christopher F
authors.initials: CF
authors.lastname: Reiche
authors.affiliation: Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Gemming
authors.affiliation: Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany; Institut für Festkörperphysik, Technische Universität Dresden, 01062 Dresden, Germany.
authors.forename: Bernd
authors.initials: B
authors.lastname: Büchner
authors.affiliation: Institut für Festkörperelektronik, Technische Universität Dresden, 01062 Dresden, Germany.
authors.forename: Gerald
authors.initials: G
authors.lastname: Gerlach
authors.affiliation: Leibniz Institute for Solid State and Materials Research IFW Dresden, Helmholtzstr. 20, 01069 Dresden, Germany.
authors.forename: Thomas
authors.initials: T
authors.lastname: Mühl
keywords: cantilever magnetometry; coupled oscillator; iron-filled carbon nanotube; magnetometry; signal enhancement