Ultrafast Surface Plasmon-Polariton Logic Gates And Half-Adder

We present studies on ultrafast interactions of multiple coherently excited surface plasmon-polaritons (SPPs) in waveguiding systems and on plane metal films. SPPs are excited by local scattering of laser light on surface nanostructures consisting of polymeric or metallic ridges. SPP interaction and scattering effects are investigated by temporally resolved leakage radiation microscopy. We further demonstrate ultrafast interactions of coherently excited SPPs and light beams in complex dielectric waveguides [3]. Coherent control of SPP and light interactions further allow for the construction of ultrafast low-power SPP switches and all-optical gate structures. These structures were investigated experimentally regarding their efficiency depending on their geometrical properties. The measurement results have been compared with FDTD simulations of the same structures and were used to design novel plasmonic half adders which functionality has been demonstrated experimentally. References: 1) C. Reinhardt et al., Optics Letters 31, pp. 1307-1309, 2006 2) C. Reinhardt et al., Applied Physics A 89, pp. 321-325, 2007 3) T. Birr et al., Optics Express 23, 31755 2015.