For many decades now, experts in the field of seemingly ever-speculating theoretical physics expected the existence of a kind of matter that was a combination of wave and particle. Subatomic physicists had already observed the strange behavior of electrons, and how they seemed to exist rather in clouds of probability rather than at individual points, like normal particles, however an entire substance maintaining a wave-particle like form was unheard of (Electrons Act Like Waves). The theorists dubbed their conjectured state “Bose-Einstein condensate”. Eventually, as its history will tell, the Bose-Einstein condensate was yielded from experiment, inspiring scientists all over the world to hypothesize for new experiments and applications for the now-proven state of matter, though currently its existential conditions are arduous. From its theoretical beginnings to the perhaps near future, the Bose-Einstein condensate has intrigued research and always foretold great possibility.
The story of this unfathomably unusual state begins with the rising academic and scientist Satyendra Nath Bose. Bose was born in 1894 in Calcutta, India, to a family of seven children. He efforts in academia, from an early age, ascended him to Presidency College in India, where he completed his first degree, in Mixed Mathematics. Two years later, in 1915, he earned Master of Science, of the same subject, in Calcutta University. He performed so well that to this day, his scores on the exams have not been surpassed. In 1921 Bose joined the department of physics in Dhaka University. After establishing several new departments, he wrote a paper deriving Planck’s quantum radiation law in 1924. Bose was already aquatinted with Einstein’s theories and person, so he mailed his paper to Albert who took interest immediately and published it there in Germany. Eventually, Bose was invited to work in X-ray and crystallography labs in Europe. Together, they developed the idea of extending Bose’s ideas about electron’s quantum properties to atoms, the initial prediction of a Bose-Einstein condensate. Essentially, if it was possible to slow the movement of individual atoms enough, they would act display quantum and electron-like Much research into quantum mechanics and subatomic physics was yet to be done at the time, but the notion was not lost (Satyendra Nath Bose Biography).
Finally, in 1995, Carl Wieman, Eric Cornell, and a group of collaborators proved the existence of the Bose-Einstein condensate. Through the advanced technique of magneto-optical trapping, the scientists were able to create a fleeting instance of Bose-Einstein condensation with a sample of Rubidium-87 atoms (their apparatus is diagrammed in Figure 1). The condensate was illuminated with a laser to illustrate the velocity distribution of atoms in the rubidium cloud, as shown in Figure 2. At last, the world of physics and chemistry could agree that atoms themselves could be induced into quantum confusion, proven by maybe the first instance of the state ever occurring in our universe (The Discovery of Bose-Einstein Condensation: Confirmation After 70 Years).
When Einstein first contemplated the prospect of an electron having a position in space only as a probability, he famously stated “God does not play dice” (Why did Einstein say 'God doesn't play dice’?). This, it seems, does not only turn out to be the case with electrons after all, but also with atoms when they reach a critical temperature. The atoms’ energy has to be so low, however, that it hovers only 1.7 × 10−7 K higher that absolute 0 (which has never been reached) in the case of the Rubidium that Wieman and Cornell used (Perkowitz). To understand why this occurs, one must be familiar with boson and fermions.
All subatomic particles, as Bose observed during his research in 1924, fall into one of two categories: those with integer quantum spin numbers and those with odd, half-integer quantum spin numbers; photons, having the integer spin of 1 are bosons and electrons, having a spin of 1/2, are fermions. The Pauli Exclusion Principle dictates additionally that all fermions repel one another, reflected in the fact that all electrons have different quantum numbers (e.g. energy level). Bosons, on the other hand, don’t have any restrictions on the proximity of them that can occupy the same quantum properties. Therefor, if a group of even-spinning “bosonic” atoms are set to the same energy level, they will share a quantum state and act as a “wave” of atoms. (Perkowitz)
As a collective mass of quantum state, these atoms have shown to display a few important quantum properties. Firstly, the Bose-Einstein condensate acts much like a light wave of photons; Bose-Einstein condensates enact quantum interference on each other. Quantum interference is when the delocalization of particles in something lets the particles interact with everywhere they have a probability of being, as can be shown by a detection of a greater amount of particles in an area where two “spheres” of probable existence for two samples overlap. Another property is quantum tunneling – a small amount of a Bose-Einstein condensate may travel across a barrier uncrossable by a normal particle. A third fascinating ability of this type of condensate is to exhibit a Josephson Effect. The Josephson Effect is simply the quantum tunneling between two substances, creating a “weak link” between them (What are the properties of a Bose Einstein Condensate?). Finally the very-likely most curious of all its traits is a Bose-Einstein condensate’s slowing of light passing through it (Physicists Slow Speed of Light). Through all of these properties previously so hard to experiment with – they were confined to tiny subatomic particles. Bose-Einstein condensates prove particularly interesting for they not only occur in larger, more-workable forms, but also under potentially more-accessible conditions. (What are the properties of a Bose Einstein Condensate?)
Rising in the field of both theoretical and applied quantum physics is the concept now construction of the quantum computer. A quantum computer uses quantum bits (qbits) to do computations, letting the machine process all different pathways of logic almost instantly. Currently, primitive quantum computers can operate in strict vacuums at near-0K temperatures, but Bose-Einstein condensates propose alternatives. A Bose-Einstein condensate can be created at room temperature, as scientists in IBM’s Binnig and Rohrer Nano Center have done, using cooling with laser and mirrors; the condensate lasted only a few seconds but more enduring methods are already being tested. (Bose-Einstein condensate Made at Room Temperature for First Time).
Quantum computers using qbits made of Bose-Einstein condensates can make use of the Josephson Effect to transmit quantum information, across thin barriers, between themselves. This is an extremely efficient and convenient way for quantum computers function for it keeps the qbits in isolation but allows communication between them with minimal interference and information-loss (Bose-Einstein condensate Made at Room Temperature for First Time). A future quantum computer that conducted on laser-induced Bose-Einstein condensate qbits would be able to be used to room temperature and within a reasonably small machine, for large the large sensor devices needed to detect minuscule quantum fluctuations in subatomic systems would not be needed for molecule-sized Bose-Einstein condensates.
For 70 years the mystical Bose-Einstein condensate subsisted solely in theory, but now science has more than proved its existence, it has brought it into the everyday 25º room environment. The future promises much in the way of uses, but the Bose-Einstein condensate also opens the door to new pathways of speculation and theory that were the myths of myths just a decade ago, and some of those doors are even being opened today. Superfluids, of which a Bose-Einstein condensate is a type, also contain types of fermions that create pairs in order to overcome their natural aversions. Superconductivity, a phenomenon of 0-resistance electrical-conductivity in a substance first recorded in 1911 by Heike Kamerlingh Onnes, is now recognized as linked to larger principals of quantum physics like SQUIDS and the Josephson Effect (The History of Superconductors). One day, impossibly fast quantum computers and ultra-sensitive Bose-Einstein condensate-laser sensors to go along with them may be produced – the world of materials and machines will have advanced in bounds, all because of the theory on and the material itself of the Bose-Einstein condensate.
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