ABSTRACT
This chapter gives an overview of the use of biological molecules in optically coupled molecular electronic devices, with an emphasis on the use of the protein bacteriorhodopsin in optical memories and optical computing devices. It describes the use of this protein in selected applications that include holography, spatial light modulators, neural network optical computing, and volumetric and associative optical memories. There are significant advantages inherent in the use of biological molecules, either in their native form or modified via chemical or mutagenic methods, as active components in optoelectronic devices. Optically coupled devices based on bacteriorhodopsin are driven by linear (one-photon) or nonlinear (two-photon) excitation. A majority of these devices operate by switching between two of the intermediates that populate the complex photocycle of the protein. Two-photon three-dimensional optical addressing architectures offer significant promise for the development of a new generation of ultra-high-density random access memories. The chapter illustrates the optical design of a two-photon three-dimensional optical memory.
