Speaker: Ming Su
Affiliation: University of Queensland

Abstract

Integrated photonics has been revolutionising the optical communication and application space. Fabrication of light sources, detectors and optical circuits on chip and integration with electronic circuits has been driving novel products and application through miniaturisation, compactness and robustness. First steps have been undertaken to harness this potential for quantum optics with demonstrations of on chip generation, processing, and detection of quantum states of light, with ever increasing level of complexity. Current devices already approach 1,000's of components on millimetre-scale footprints with Silicon-on-Insulator technology. The crux lies in the required efficiency to be feasible for quantum photonics, and current circuits frequently lose more than 90% of input signal - not good enough for quantum information. To reach scalability of these devices we need to develop compact ultralow loss passive components and realise fast, compact, and low-power phase shifter with ultralow loss. We try to tackle those crucial issues by utilizing photonic inverse design method to design more efficient photonic devices and exploring the use of ultralow loss materials such as lithium niobate, silicon nitride and silicon carbide. We show that by using inverse design, our grating coupler can theoretically reach up to 83% coupling efficiency on silicon nitride wafer, and transmission of our compact waveguide crossing is up to 97%. Those promising results are the first step towards ultralow-loss large-scale integrated quantum photonics circuits suitable for quantum information.

About Physics Seminars

The weekly Physics Seminar series focuses on a broad range of physics research within SMP, along with frequent presentations from visiting researchers. Seminars are usually scheduled for 1.00pm on Tuesdays.

The talks are typically more specialised than a colloquium but are often attended by staff and PhD students across a broad range of areas. Speakers are thus encouraged to include introductory material in the talks.

All SMP researchers and HDR students are encouraged to speak. Please email Lewis Williamson to register your interest.

The seminars are open so there is no need to register your attendance.

Venue

Physics Annexe (06)
Room: 
407 (and via Zoom https://uqz.zoom.us/j/94116861984)