Bose-Einstein Condensate: Properties, Applications

He Bose-Einstein condensate it is a state of matter that occurs in certain particles at temperatures close to absolute zero. For a long time it was thought that the three possible states of aggregation of matter were solid, liquid and gas.

Then the fourth state was discovered: plasma; and the Bose-Einstein condensate is considered the fifth state. The characteristic property is that condensate particles behave as a large quantum system rather than as they usually do (as a set of individual quantum systems or as a grouping of atoms).

In other words, it can be said that the whole set of atoms that make up the Bose-Einstein condensate behaves as if it were a single atom.

Origin

Like many of the more recent scientific discoveries, the existence of the condensate was theoretically deduced before there was empirical evidence of its existence.

Thus, it was Albert Einstein and Satyendra Nath Bose who theoretically predicted this phenomenon in a joint publication in the 1920s. They did so first for the case of photons and then for the case of hypothetical gaseous atoms.

The demonstration of its real existence had not been possible until a few decades ago, when it was possible to cool a sample at temperatures low enough to prove that what the equations anticipated was true.

Satyendra Nath Bose

Obtaining

The Bose-Einstein condensate was obtained in 1995 by Eric Cornell, Carlo Wieman and Wolfgang Ketterle who, thanks to this, would end up sharing the 2001 Nobel Prize in Physics.

To achieve the Bose-Einstein condensate, they resorted to a series of experimental techniques of atomic physics, with which they managed to reach the temperature of 0.00000002 degrees Kelvin above absolute zero (temperature much lower than the lowest temperature observed in outer space). .

Eric Cornell and Carlo Weiman used these techniques in a diluted gas composed of rubidium atoms; For his part, Wolfgang Ketterle applied them a short time later on sodium atoms.

The bosons

The name Boson is used in honor of the Indian-born physicist Satyendra Nath Bose. In the physics of particles, two basic types of elementary particles are considered: bosons and ferminions.

What determines whether a particle is a boson or a fermion is whether its spin is integer or half-integer. Ultimately, bosons are the particles responsible for transmitting interaction forces between fermions.

Only the bosonic particles can have this state of Bose-Einstein condensate: if the particles that are cooled are fermions, what is achieved is called a Fermi liquid.

This is because bosons, unlike fermions, do not have to comply with Pauli's exclusion principle, which states that two identical particles can not be in the same quantum state at the same time.

All atoms are the same atom

In a Bose-Einstein condensate all atoms are absolutely equal. In this way, most condensed atoms are at the same quantum level, descending to the lowest possible energy level.

By sharing this same quantum state and having all the same (minimum) energy, the atoms are indistinguishable and behave as a single"superatom".

Properties

The fact that all the atoms have identical properties supposes a series of determined theoretical properties: the atoms occupy a same volume, disperse light of the same color and a homogenous medium is constituted, among other characteristics.

These properties are similar to those of the ideal laser, which emits a coherent light (spatially and temporally), uniform, monochromatic, in which all the waves and photons are absolutely equal and move in the same direction, which is ideally not dissipate

Applications

The possibilities offered by this new state of matter are many, some really amazing. Among the current or developing, the most interesting applications of Bose-Einstein condensates are the following:

- Its use together with atom lasers to create high precision nano-structures.

- Detection of the intensity of the gravitational field.

- Manufacturing atomic clocks more accurate and stable than those that currently exist.

- Simulations, on a small scale, for the study of certain cosmological phenomena.

- Applications of superfluidity and superconductivity.

- Applications derived from the phenomenon known as slow light or slow light; for example, in teleportation or in the promising field of quantum computing.

- Deepening the knowledge of quantum mechanics, carrying out more complex and non-linear experiments, as well as the verification of certain theories recently formulated. The condensates offer the possibility to recreate in the laboratories phenomena that happen to light years.

As you can see, Bose-Einstein condensates can be used not only to develop new techniques, but also to refine some techniques that already exist.

Not in vain they offer great precision and reliability, which is possible due to their phase coherence in the atomic field, which facilitates a great control of time and distances.

Therefore, the Bose-Einstein condensates could become as revolutionary as the laser itself was, since they have many properties in common. However, the great problem for this to occur lies in the temperature at which these condensates are produced.

Thus, the difficulty lies both in how complicated it is to obtain them and in their costly maintenance. For all these reasons, most of the efforts currently focus mainly on their application to basic research.

Condensed Bose-Einstein and quantum physics

The demonstration of the existence of Bose-Einstein condensates has offered a new and important tool for the study of new physical phenomena in very diverse areas.

There is no doubt that its coherence at the macroscopic level facilitates both the study, understanding and demonstration of the laws of quantum physics.

However, the fact that temperatures close to absolute zero are necessary to achieve this state of matter is a serious inconvenience to get the most out of its incredible properties.

References

1. Condensate of Bose-Einstein (n.d.). In Wikipedia. Retrieved on April 6, 2018, from es.wikipedia.org.
2. Bose-Einstein condensate. (n.d.) In Wikipedia. Retrieved on April 6, 2018, from en.wikipedia.org.
3. Eric Cornell and Carl Wieman (1998). Condensed Bose-Einstein,"Research and Science".
4. A. Cornell & C. E. Wieman (1998). "The Bose-Einstein condensate". Scientific American .
5. Bosón (n.d.). In Wikipedia. Retrieved on April 6, 2018, from es.wikipedia.org.
6. Boson (n.d.). In Wikipedia. Retrieved on April 6, 2018, from en.wikipedia.org.