Optical and magnetic measurements of gyroscopically stabilized graphene nanoplatelets levitated in an ion trap

The authors present magnetic moment measurements of a levitated graphene nanoplatelet, observing two mechanisms of interaction with a magnetic field, one diamagnetic and one due to the particle's rotation. These observations are made possible by gyroscopically stabilizing the nanoplatelet using radio-frequency electric fields, achieving control of the rotation frequency up to 100 MHz while it is held in an electric field trap at high vacuum. Levitation avoids substrate effects and clamping losses entirely, while gyroscopic stabilization provides unparalleled torque sensitivity. The method is expected to be generalizable to other two-dimensional materials and nanoparticles and may be incorporated into optomechanics experiments.