Demonstration of extremely low switching energies using new n-i-p-i-based smart pixels

摘要

We report on recent theoretical and experimental results on n-i- p-i based smart pixels. We present first results on dynamical switching in these devices. In particular, we present 1.9 ns switching times at an optical power of 880 $mu@W for the photoconductive switch. This corresponds to a total switching energy of 1.7 pJ or 2.4 fJ/$mu@m$+2$/ relative to the device area. A contrast of the electronic output signal larger than 10$+7$/ and a maximum dc gain exceeding 10$+6$/ is achieved. For an optical NOR gate - composed of a photoconductive switch and an electroabsorptive n-i-p-i modulator - we were able to demonstrate operation at optical switching energies of 2 pJ and switching times of 1 $mu@s. This corresponds to an opto-optical gain (fan out) of 750. The switching contrast of the optical output signal is 4.5:1.