The overall objective is to develop an opto-electronic module based on a gain switched Photonic Integrated Circuit (PIC)-based optical frequency comb source suitable for high resolution optical frequency metrology.

 

This activity will focus on the development of a photonic integrated circuit (PIC) based version of the de-risked novel light source. As with the bench-top version, the chip consists of three stages and operates as follows. Stage one produces an optical comb centred on 795nm and with a wavelength spacing of 6.835 GHz. In stage two, the demultiplexer stage, this comb is split into two equal paths each of which lead to an injection locked laser. The two injection locked lasers are tuned to select a pair of adjacent wavelengths from the comb. In stage three, these two wavelengths are coupled back together to produce a dual-tone coherent signal in a single waveguide. The ability to perfectly match the length of the demultiplexer arms will overcome the only issue identified in the de-risking activity.

Within this activity, the chip will be packaged in a custom optical package, and mounted on a custom designed driver board offering the same functionality and feedback control as the breadboard based driver unit from the de-risk phase, but in a greatly reduced form-factor.

 

The tasks required to achieve this overall objective include:

• To design and model 795nm wafer material suitable for the chip development

• To design and model the dedicated chip based on the data from the above step

• To produce a set of masks for processing the wafer and fabricating the PICs

• To test and characterise the chips

• To design and produce a custom optical package for the chips

• To design and produce an electronic driver and control board to accommodate the packaged chip

• To apply the complete opto-electronic module to applications in the domain of coherent population trapping for high frequency optical metrology in order to validate the technology.