Unnithan runs a sensor-engineering group spanning plasmonic colour filters and metasurface-based CMOS image and spectral sensors, thermal/hyperspectral cameras, machine learning on sensor data, and — the relevant thread here — the engineering and packaging of quantum diamond magnetometers, in a joint programme with the Melbourne physics groups and Phasor Innovation aimed at navigation, subsurface sensing and eventual healthcare use. He has extensive industry links (Hort-Eye, KDH) and an entrepreneurial orientation. Positioned against the established body of NV-ensemble quantum sensing work — DEER, nanoscale NMR and T1 relaxometry protocols operating at pT/sqrt(Hz) field sensitivity — his role in that collaboration is on the readout, optics and integration side rather than the spin physics, i.e. turning a laboratory pT/sqrt(Hz) NV ensemble into a fielded instrument. Caveat against the stated preference: this group is substantially device-fabrication and product-oriented rather than sensitivity-limited fundamental measurement.