Scientists at the Georgia Institute of Technology have applied a process called "squeezing" to one of the smallest building blocks of matter in an attempt to fully understand the nature of atoms.
The Heisenberg Uncertainty Principle is a theory in quantum mechanics that says that the measurements of the position and the momentum of an object cannot be simultaneously known within the same degree of certainty.
Therefore, there must be some uncertainty in either the specific location or the specific momentum of an object when they are both being calculated. This uncertainty is usually depicted using a circular graph, such that as the uncertainty in one measurement decreases, the uncertainty in the other increases, and vice versa.
Squeezing is a process of manipulating the graph of uncertainty for measurements, such as those defined by the Heisenberg Principle. The circle is "squeezed" from one direction to form an ellipse, effectively decreasing the range of uncertainty for one calculation, while increasing the range of the other.
Since the area inside the ellipse is the same as that inside the circle, no fundamental change has occurred, only there is now an improved accuracy in measuring one of the properties of the principle.
Squeezing has been used in the past to measure the properties of microscopic particles, such as atoms and photons, the quantifiable particles of light used in quantum mechanics. It has also been used to increase the accuracy of machines, such as atomic clocks and the magnets essential to the proper functioning of magnetic resonance imaging (MRI) in medicine.
At Georgia Tech, squeezing has been applied to the nematic tensor, a particle used to describe the rubidium atoms in Bose-Einstein condensates (BECs). BECs are a state of matter created by the exposure of a gas to very low temperature close to absolute zero, the theoretically lowest temperature possible.
Under such conditions, the atoms' properties change such that their quantum mechanical properties, which are usually only occurring microscopically, become observable on a macroscopic scale.
For years, scientists have been squeezing atoms to the point that their quantum identity can now be defined by two states. The BSE states have been squeezed into three quantum states, an unhelpful number. But at Georgia Tech, scientists have been working on squeezing the quantum states so that atoms can only be defined in one way, by the nematic tensor.
The squeezing is done experimentally by entangling some of the BEC atoms by a process of colliding 40,000 of them. The collision allows the entanglement in which the quantum state of one atom facilitates a similar quantum state in the other entangled atoms. This, therefore, facilitates the squeezing.
This reduction in uncertainty in the ability to measure the quantum state of atoms can have important implications in the measurement of magnetic fields.
