This non-linear world (1979)

Light beam.

Model of molecular crystal lattice.

Concept of linearity.

Refraction of light in a prism.

Experiment demonstrating the law of light reflection.

A beam can be divided into parts, but in a homogeneous medium it always remains straight.

Air and water can reduce its strength, but never change its color.

It was believed that light is not able to disrupt harmonic oscillations in the molecules of a substance, so its brightness changes proportionally.

Pendulums.

Photograph by S.I. Vavilov.

In the mid-20s, he discovered the unusual behavior of light rays.

Experiment with a condensed spark.

The beam, passing through uranium glass, disproportionately changed its brightness.

True, the nonlinearity was barely noticeable.

Photograph of Vavilov at the devices.

If Vavilov could further increase the brightness of the source, he would find that the dark glass becomes transparent, and the dependence curve steeply rises.

This meant that bright light strongly rocked the molecular system, and therefore changed the optical properties of the substance.

Pendulum.

Vavilov realized that the effect he had discovered was not unique, but that a new science was emerging.

Nonlinear optics.

Devices on the laboratory shelves.

In his opinion, such processes occurred on the stars.

Space.

A rocket rises into space.

A powerful source needed for research in nonlinear optics appeared 40 years later. A. M. Prokhorov and N. G. Basov are awarded the Nobel Prize for the laser.

It turned out that the angle of incidence of a laser beam is not always equal to the angle of reflection.

Experiment.

The environment can change the color of the beam.

Red and green laser beams generate another beam - blue.

At high light power, the beams acquire the ability to self-focus, stretch into a thin thread.

A cartoon explaining the applied significance of a laser.

It was proposed to use a laser beam to break pre-selected bonds in molecules, to create substances with specified properties.

The ability to influence DNA molecules or look into the storehouses of nature.

View of Stalin's skyscraper from the Moscow State University observatory.

A team of nonlinearists was created at the Department of Wave Processes of the Physics Faculty of Moscow State University.

It was headed by R. V. Khokhlov, Doctor of Physical and Mathematical Sciences.

Photos of R. V. Khokhlov with his colleagues.

Rem Khokhlov is a mountain climber.

A pilot lands an airplane.

Lasers began to be used in optical rangefinders and locators, fiber-optic communication lines.

Lasers process heat-resistant materials.

Scientific equipment.

Laser installation.

A laser beam of a strictly defined color and can affect molecules in a very limited frequency range.

Photo of Khokhlov with his associates.

Khokhlov expressed the idea of the possibility of smoothly changing the frequency of lasers using nonlinear optics.

The environment can change the light of the beam, and therefore the frequency.

Experiment: a laser emits an invisible infrared beam.

Let's put a crystal in its path and the beam becomes visible.

It's not that simple.

The crystal's position relative to the beam is arbitrary, and such crystals did not exist in nature.

The crystals had to be grown in the laboratory.

A sample of such a crystal.

Operation of a parametric light generator.

The frequency palette of light becomes richer.

Molecular lattice against the background of piano strings.

Photograph of the creators of the generator R.V. Khokhlov and S.A. Akhmanov.

The scientists were awarded the Lenin Prize for developing the fundamentals of nonlinear optics and a parametric light generator.

Rem Khokhlov at the 6th Conference of the International Association of Universities.

Classes at Moscow State University.

A field covered with grain crops.

Scientists believe that a green leaf of a plant is a battery where the sun's energy is converted into a flow of electrons.

This process is instantaneous.

A lightning discharge is a thousand times slower.

Light is reflected in a drop of water on a leaf.

Plants in a laboratory.

Nonlinear optics made it possible to create a laser with a short and powerful flash.

During the flash, the light manages to travel only a third of a millimeter.

Experiment.

View of the harvest through a plant leaf.

The sea.

Nonlinear optics finds application in environmental protection.

Ships at sea.

A laser beam, like a giant probe, penetrates the depths of the ocean.

An echo signal reports the smallest particles in its path.

Sonar readings.

The state of the environment is determined directly on the vessel.

Scientists are trying to obtain energy without polluting the environment.

Scientific equipment for obtaining plasma, a source of colossal energy.

A view of the laboratory equipment for obtaining a thermonuclear reaction. 32 laser beams are directed at one point, where the fusion of deuterium and tritium nuclei will occur.

Photo by S.I. Vavilov.

Vavilov's experiment.

Measuring equipment in Vavilov's time.