A. Andreoni et al., Boolean algebra operations performed on optical bits by the generation of holographic fields through second-order nonlinear interactions, REV SCI INS, 72(6), 2001, pp. 2525-2531
Boolean algebra operations such as AND or XOR are performed on optical bits
encoded as amplitude modulations in two wave fronts that are made interact
in a crystal (beta -BaB2O4) endowed with second-order nonlinearity. If the
corresponding wave fields are at the same frequency omega and the crystal
is tuned for the phase-matched generation of 2 omega, we show that the gene
rated wave front reconstructs a holographic image containing the outputs of
the desired operations. Since a nearly diffraction-limited optical resolut
ion can be easily achieved in the holographic image at 2 omega, a correspon
dingly high density of data is encodeable in the wave front at omega playin
g the role of object wave front. The experiments demonstrate the feasibilit
y of the operation of a parallel half-adder performing the sum of multiple
data with a one-digit binary number, which is encoded in the reference wave
front. (C) 2001 American Institute of Physics.