Fig. 2.
(a) Sample mounted on the stage of an inverted microscope: A microdroplet of the MNB solution, surrounded by squalene and sandwiched between two coverslips, was mounted on an aluminium holder and positioned in the center of two orthogonal Helmholtz coils; see also main text for details. (b) Representative snapshots of a single rotating MNB in an aqueous microdroplet when driving it with an alternating magnetic field ( Hz); see supplementary movie 1 for the full time series.