Diamond turning is the process of producing optical quality surfaces by precision machining with a diamond cutting-bit. The technique is a cornerstone process for the fabrication of precision optical elements such as aspheric lens moulds for compact cameras and fibre couplers. In a research setting, diamond-turned optics are used in a variety of novel ways to shape optical fields.

The ANU possesses a diamond turning machine and in this seminar I will present an overview of the capabilities of our machine and some examples of the research projects that it is enabling. A core focus of our research has been to fabricate compact optical resonators directly from nonlinear optical crystals. I will discuss how we make these along with some of the advantages that they hold over more traditional resonators.

Another focus has been to build-out collaborations with other research groups at the ANU, in Australia, and internationally. One such project is the production of concave spherical reflectors that are designed to enable the high-efficiency coupling of single photons to a single trapped ion. Another is to make diffractive optics that generate optical vortices with topological charges of up to 10,000 to investigate entanglement in a high-dimensional basis. I will present the techniques that we use to make these and other precision optics along with some of the results that have been achieved.

Geoff Campbell has recently completed his doctoral work at the ANU in the Department of Quantum Science and is continuing research as a postdoctoral fellow. His thesis topics were on optical quantum memory in atomic ensembles and nonlinear optics in diamond turned resonators.