Quantum electronics

Quantum electronics was born when a new method was proposed for generating and amplifying radio waves by the use of quantum micro-systems, molecules, atoms and so on. This method has proved very fruitful and gave good results.

On the basis of radio-frequency quantum generators clocks have been made that measure time with an accuracy of one second per 300 years. Modern scientific achievements make possible the manufacture of clocks which measure time with an even higher accuracy, namely: one second per tens of thousands of years. Such superprecise generators can be applied for aerial and sea navigation.

Of no less importance are the quantum amplifiers, they considerably increase the sensitivity of radio receivers. Quantum amplifiers operate at temperatures close to absolute zero, and radio receivers developed on the basis of quantum amplifiers are tens and even hundreds of times more sensitive than conventional receivers. This considerable increase in sensitivity opens up great future for radar, radio navigation, space radio communication, radio astronomy and other fields of science and technology.

Perhaps the most interesting thing about semiconductor lasers is that they can transform electrical energy directly into light wave energy. They do this with an efficiency approaching one hundred per cent. The development of powerful highly-efficient semiconductor lasers will considerably raise the power efficiency of a number of technological processes. Calculations and experiments show that even superhard substances such as diamonds, rubies, hard alloys and so on can be worked profitably by means of ruby lasers.

Semiconductor quantum generators occupy a special place among the optical quantum generators. The size of a ruby crystal laser comes to tens of centimetres. Ruby crystals about ten centimetres long can intensify light ten times. The same results can be obtained from semiconductor crystals only a few microns long.

Semiconductor laser is a few tenths of a millimetre long, whereas the density of its radiation is hundreds of thousands of times as great as that of the best ruby lasers. Semiconductor lasers operate under pulse and permanent regimes. It is very easy to control the generator oscillations, to modulate its radiation by simply changing its feed current. The high-frequency radiation of optical generators makes if possible to transmit an enormous flow of informa­tion. This is of great significance for the advancement of communication techniques. The small dimensions of the semiconductor laser make it especially suitable for use in superspeed computers.

Theoretical calculations have shown that devices similar to semiconductor lasers can also transform the energy of light radio waves into electrical energy with an efficiency of close to 100 per cent. This means that electric power may be transmitted over considerable distances with negligible losses without the use of transmission lines. The high efficiency of semiconductor lasers opens up possibilities of developing extremely economical sources of light.

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