Three-port reversible logic.
Reliable optical switching at a nonlinear interface is obtained from the symmetry of a two-beam information lossless interaction. The device configuration, which is noise insensitive and cascadable, performs bit-conserving inverse and product functions reversibly. Numerical computations of the optical field redistribution at a dual-beam interface with opposing diffusive Kerr nonlinearities show the first reported evidence of Gaussianlike switching with high contrast.