Institute of Physics, University of Münster, Münster, Germany

J. Feldmann, H. Gehring, M. Stappers & W. H. P. Pernice

Department of Materials, University of Oxford, Oxford, UK

N. Youngblood, X. Li & H. Bhaskaran

Laboratory of Photonics and Quantum Measurements, Swiss Federal Institute of Technology Lausanne (EPFL), Lausanne, Switzerland

M. Karpov, X. Fu, A. Lukashchuk, A. S. Raja, J. Liu & T. J. Kippenberg

IBM Research Europe, Rüschlikon, Switzerland

M. Le Gallo & A. Sebastian

Department of Engineering, University of Exeter, Exeter, UK

C. D. Wright

Center for Soft Nanoscience, University of Münster, Münster, Germany

W. H. P. Pernice