Microfluidics for the thermal control of Photonics Integrated Circuits

Contemporary optical communications infrastructure features Photonics Integrated Circuits (PICs), optoelectronic devices that serve a range of applications — for example, transceivers for high-bandwidth data transmission via optic fibres. PICs represent a stringent packaging challenge, however, particularly in terms of their high device-level heat fluxes and tight requirements for thermal control. A Horizon 2020 consortium entitled ‘Thermally Integrated Smart Photonics Systems (TIPS)’ is currently working on the development and demonstration of a highly integrated PIC platform. This paper presents a selection of recent work on microfluidics cooling for PIC applications, focusing on primary heat exchange and aspects of fluidic pumping. The thermal behaviour of two heat exchangers is detailed — a channel-confined inclined jet, and a confined, normally-impinging, slot jet — and the pressure-flow characterisation of a range of planar fluidic diodes for the rectification of oscillatory pumps is reported.