Viktor K. Salakhutdinov

High-speed multichannel optical switching

The programmable interconnection between N input and N output channels based on a matrix of microholograms is considered. Such a system can be used for optical switching having high speed, about gigabits-per-second. An example of such a system using bacteriorhodopsin film is investigated both theoretically and experimentally. The thickness of bacteriorhodopsin was 50 micrometers and the cell size 3cmx2cm. To maintain interconnects each microhologram was regenerated by means of a routing system composed of a He-Ne laser, deflectors and optical elements. Experimentally, 20 channels were used. The diameter of the microhologram was 1mm, and the diffraction efficiency was about 2%. The tests and calculations show the possibility of arranging 104 switching channels with speed about 1 gigabit per second.

High-capacity optical spatial switch based on reversible holograms

A scheme is presented for an optical spatial switch in which independent and arbitrary switching is realized using diffraction of light beams by a programmable microhologram array (MA). It is shown that a bacteriorhodopsin film can be used as a recording medium for an MA. If the throughput of each channel is up to several Gbit/s, the capacity of such a switch can reach 10 4 x 10 4 channels, with the time of an arbitrary switching not more than 100 ms. The experimental results given prove the possibility of implementing a switch having these characteristics

Bacteriorhodopsin as a fast recording medium

Optical and holographic properties of bacteriorhodopsin recording materials are considered. The use of short light pulses for recording in BR materials is shown to lead to a decrease in their sensitivity and diffraction efficiency. The relationship between BR properties and the write pulse width is shown to depend on the photosensitivity of BR short-living forms.

Reprogrammable interconnects based on overrecordable holograms

The problem of interconnecting a large number of information channels according to a preset law, using an array of reprogrammable microholograms, is considered. The dynamic characteristics of the holograms in the process of retrieving are investigated. Experimental results demonstrating this method of interconnects are presented.

Holographic interconnects using bacteriorhodopsin material

A scheme of an optical switch using a matrix of reprogrammable holograms is discussed. The light from each input channel is deflected to an output channel with a separate microhologram. The microholograms are recorded and overrecorded with two acousto-optical deflectors on a bacteriorhodopsin photo medium. The experiments have been carried out on a prototype with 20 X 20 channels. As shown, the capacity of such a switch can be increased up to 104 X 104.

Diffraction efficiency of BR holograms under thermal exposure

The change of the dark relaxation rate of the bacteriorhodopsin (BR) hologram diffraction efficiency with write pulse width is considered. The heating of the BR film with light pulses is shown to be the cause. The effect of thermal exposure can be reduced by increasing the hologram spatial frequency.

Use of the photoinduced dynamic lens for enhancing the resolution of an optical addressing system

The method of increasing the resolution of an optical addressing system is offered. A dynamic lens which is induced by a controllable light beam in a photochrome dye is used. The performance of the dynamic lens formed in the photochrome medium has been investigated. The findings of an investigation into a reversable light-sensitive crown-bearing medium are presented. It has been found experimentally that the resolution of the optical addressing system can be increased by an order of magnitude if the solution of a phitichrome crown-bearing dye is used.

Dynamic optical elements for memories and neural networks

Nonlinear properties of a crown ester-based photochromic medium and the formation of a thermal lens under laser radiation have been studied. Such a thermal lens is shown to provide the ability to increase the number of resolved deflector elements, which is important for storage systems and neural networks.

Phase characteristics of bacteriorhodopsin-based photocarriers in a gelatin matrix

The method of measuring phase characteristics of dynamic carriers is considered. BR photoinduced isomerism influence on the refractive index of BR-based carriers is studied. The photoinduced change in refractive index of the BR-based photocarrier is shown to reach 3.5 (DOT) 10-4 at wavelength 0.44 micrometers .

Nonlinear properties of a crown-bearing dye: optical addressing system as its basis

Optical characteristics of dynamic lens formed by light in the photoreversable medium are considered. The results of investigating non-linear optical crown-ester-based photoreversible media are presented. The use of the crown-ester-based photochromic medium is shown to enhance the resolution of an optical-addressing system almost by an order of magnitude.