An integrated optical parallel adder as a first step towards light speed data processing
Integrated optical circuits with nanophotonic devices have attracted significant attention due to its low power dissipation and light-speed operation. With light interference and resonance phenomena, the nanophotonic device works as a voltage-controlled optical pass-gate like a pass-transistor. This paper first introduces a concept of the optical pass-gate logic, and then proposes a parallel adder circuit based on the optical pass-gate logic. Experimental results obtained with an optoelectronic circuit simulator show advantages of our optical parallel adder circuit over a traditional CMOS-based parallel adder circuit.
Abstract In many applications, such as atmospheric chemistry, large systems of ordinary differential equations (ODEs) with both stiff and nonstiff parts have to be solved numerically. A popular approach in such cases is to integrate the stiff parts implicitly and the nonstiff parts explicitly. In this paper we study a class of implicit-explicit (IMEX) linear multistep methods intended for such applications. The paper focuses on the linear stability of popular second order methods like extrapolated BDF, Crank-Nicolson leap-frog and a particular class of Adams methods. We present results for problems with decoupled eigenvalues and comment on some specific CFL restrictions associated with advection terms.