In a recent work, published in Nanotechnology 19 205201, the authors studied the mechanisms that make possible the direct modulation of light from silicon quantum dots integrated into a MOSFET transistor. The physical principle of modulation is based on the inability of silicon quantum dots to emit light when they are in a charged state, basically due to a reinforcement of the non-radiative paths.

J Carreras et al. have been able to modulate light from silicon nanocrystals at rates of 200 Mbit/s by using boosted electrons from channels to charge the nanocrystals. The main advantages to conventional modulators include less current consumption (from the theoretical minimum of 104  A cm–2 in p-i-n modulators to 1 A cm–2 in the presented device), extremely low modulating voltages (1 V for modulation depths close to 100%) and inherent scalability.

Other interesting applications may be envisaged from the principle of high-speed control of luminescence in ultra-scaled MOSFETs, such as integrated biological sensing or single photon-on-demand emitters.