Magneto-optical plasmonic heterostructure with ultranarrow resonance for sensing applications.
Currently, sensors invade into our everyday life to bring higher life standards, excellent medical diagnostic and efficient security. Plasmonic biosensors demonstrate an outstanding performance ranking themselves among best candidates for different applications. However, their sensitivity is still limited that prevents further expansion. Here we present a novel concept of magnetoplasmonic sensor with ultranarrow resonances and high sensitivity. Our approach is based on the combination of a specially designed one-dimensional photonic crystal and a ferromagnetic layer to realize ultralong-range propagating magnetoplasmons and to detect alteration of the environment refractive index via observation of the modifications in the Transversal Magnetooptical Kerr Effect spectrum. The fabrication of such a structure is relatively easy in comparison with e.g. nanopatterned samples. The fabricated heterostructure shows extremely sharp (angular width of 0.06°) surface plasmon resonance and even sharper magnetoplasmonic resonance (angular width is 0.02°). It corresponds to the propagation length as large as 106 μm which is record for magnetoplasmons and promising for magneto-optical interferometry and plasmonic circuitry as well as magnetic field sensing. The magnitude of the Kerr effect of 11% is achieved which allows for detection limit of 1∙10(-6). The prospects of further increase of the sensitivity of this approach are discussed.
Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory, 119991, Moscow, Russia.|Russian Quantum Center, Novaya str., 143025, Skolkovo, Moscow, Russia.
Daria O
DO
Ignatyeva
Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory, 119991, Moscow, Russia.|Russian Quantum Center, Novaya str., 143025, Skolkovo, Moscow, Russia.
Grigory A
GA
Knyazev
Russian Quantum Center, Novaya str., 143025, Skolkovo, Moscow, Russia.
Pavel O
PO
Kapralov
École Polytechnique Fédérale de Lausanne, Laboratoire de Physique de la Matière Vivante, IPHYS, CH-1015, Lausanne, Switzerland.
Giovanni
G
Dietler
École Polytechnique Fédérale de Lausanne, Laboratoire de Physique de la Matière Vivante, IPHYS, CH-1015, Lausanne, Switzerland.
Sergey K
SK
Sekatskii
Lomonosov Moscow State University, Faculty of Physics, Leninskie Gory, 119991, Moscow, Russia.|Russian Quantum Center, Novaya str., 143025, Skolkovo, Moscow, Russia.
Vladimir I
VI
Belotelov