A Bose-Einstein condensate is a group of atoms cooled as close to absolute zero as possible. When they reach that temperature, the atoms have almost no energy and, as a consequence, move negligibly. At that point, the atoms begin to clump together, and enter the same energy states. They become identical, from a physical point of view, and the whole group starts behaving as though it were a single atom. This state of matter is one of the most recently discovered; theorized by Satyendra Nath Bose and Albert Einstein in 1924 it was not created in a lab until the 1990’s due to lack of technology.
The process of creating a Bose-Einstein condensate usually involves the use of rubidium gas, however, sodium gas has been used at MIT labs. First, the atoms of the element that are being put into the condensate state must be separated by being heated, around 700° in MIT labs, forcing them into the gaseous state. Second, they are put into a chamber where they can be supercooled by lasers, another cool topic that will not be gone over in this blog post. The lasers can only get the atoms down to a certain temperature, around 0.001 K, and are not enough to induce the condensate. The next step is expelling excess heat by getting rid of higher energy particles through the use of a gravitational field. Imagine all of the supercooled particles in an upright cup where the earth’s gravity is substituted with the magnetic pull. Basically, lower temperature particles hang around the bottom of the “cup” while higher energy particles are able to push against the magnetic pull, eventually being lost over the “brim” of the cup, effective lowering the overall energy of the particles left in the “cup” to sub-nanokelvin values. This temperature is around one million times hotter than outer space. This is the stage of the process where the condensate forms. As the particles lose more and more energy, it becomes harder to distinguish between them. Energy is what allows a proton to be a proton and an electron to be an electron. Without energy, they completely lose their identities and succumb to the magnetic force and clump together.
This graph illustrates the amount of virtually energy-less particles there are as the process progresses. The higher on the graph, the less energy. The white and bluish white indicates the condensate-like matter.
This may seem cool just thinking about it, but what does Bose-Einstein condensate do? Well, observing the properties of this identity-less matter may help us learn about other forms of matter, such as matter under extreme pressure, known as neutron stars, or matter with extremely high amounts of energy believed to have been created by the big bang, known as quark-gluon plasma. Along with these uses, Bose-Einstein condensate was used in an experiment led by scientist Lene Hau to slow down photons, particles that make up light, to 17 meters per second. That in itself is utterly insane. This experiment also proved that light can be stopped.
As of now, Bose-Einstein condensate is extremely hard to make and it always short-lived in the lab environment. Due to this, it currently had no commercial uses. In labs, however, the condensate continues to be experimented on and have its properties identified.
Wow Brad! This is a good and intersting post. I found it interesting that they were able to slow down photons that move at the speed of light to 17 meters per second. I didn't know that it as possible to slow lights down that slow. One thing that I didn't really understand that well are neutron stars. I get that neutron stars are matter with high amounts of energy, but my question to you is: How are neutron stars made? Matter with such high amounts of energy must take a lot of energy to make. Interesting blog post my dude!
ReplyDeleteYou see, when a star's life ends, a supernova occurs. A neutron star is a mass of almost purely neutrons that is left over from a supernova created by the death of a large star. Neutron stars are better characterized by being under immense pressure than having lots of energy, which they do have, because it's the pressure that gives the particles in the neutron star their unique properties. A neutron star is under so much pressure that it forces the electrons of the atoms that it's made up of out of their orbit around the nucleus. This allows for the out-of-orbit electrons and protons in the center of the atom to combine, canceling out charges, to form a neutron. This doesn't answer your question very well but hopefully you learned something anyway.
DeleteI forgot a key step in the creation of neutron stars. Neutron degeneracy is a property of neutrons that essentially prevents them form being compressed too closely together. At the stage of forming all of the neutrons and everything compressing, all of the neutrons in the mass are resisting being forced together. This neutron degeneracy force is so strong that, at a certain point of compression, the collapse of the neutrons stop simultaneously. This generates a huge shock wave and blows up the mass for a second time. The matter that is left after the shock wave is made of super compact neutrons and that is what is known as the neutron star.
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