Dr. Thomas Volz

Addressing spins in diamond with macroscopic microwave cavities

Grand challenge: Use nanoscale diamonds as ultra-sensitive probes of magnetic fields in industrial and biological environments.

This project is a joint effort between the groups of Dr Thomas Volz at Macquarie University Sydney and Professor Michael Tobar at the University of Western Australia. The project is geared towards a new method for addressing and manipulating solid-state spins using macroscopic microwave cavities both at liquid-helium and room temperature. Conventional methods for addressing diamond spins rely on on-chip solutions with the potential of generating too much dissipated heat, leading to drifts and undesirable heating of the sample to be investigated. The new approach is contactless and intrinsically requires much less drive power since the cavity provides a local enhancement of the circulated microwave power (approximately by the cavity Q-factor).

Nanodiamond levitation

This project combines the expertise of CI Volz’s group on manipulating NV centres in nanodiamonds and cold-atom trapping with the expertise in Molina-Terriza’s group on the trapping and levitation of nanoparticles in order to study the influence of embedded “artificial atoms” on the motion of the crystal as a whole for near-resonant trapping lasers. The ultimate goal is twofold: on the one hand, we want to design novel optical tweezers with enhanced optical forces for manipulating ultrasmall nanodiamonds in liquid, and on the other hand, we want to exploit the optical forces from the NV centres to cool the centre-of-mass motion of a levitated nanodiamond as a whole.