Physicists from the National Institute of Standards and Technology (NIST) and the University of Maryland developed a method through direct observation specific details that describe an isolated quantum system. Data obtained from this method involve finding atoms at specific locations with high spatial resolution. Details not readily available through current techniques are now possible as the technique can obtain data on a scale of tens of nanometers, which is smaller than the width of a virus. Findings were published in the journal Physical Review X.
The researchers performed the experiments at the Joint Quantum Institute (JQI) by using an optical lattice. Thousands of individual atoms were suspended by a web of laser light in order to know the probability of an atom to be at any given location. Because each individual atom in the lattice behaves like all the others, a measurement on the entire group of atoms reveals the likelihood of an individual atom to be in a particular point in space.
The JQI technique can pinpoint the possible location of the atoms way below the light wavelength used to illuminate the atoms. This is 50 times better than the capacity of optical microscopy.
"It's a demonstration of our ability to observe quantum mechanics," said JQI's Trey Porto, one of the physicists behind the research effort. "It hasn't been done with atoms with anywhere near this precision."
A wave function describes a quantum system. It provides the data needed to describe a system.
"It's the description of the system," said JQI physicist Steve Rolston, another of the paper's authors. "If you have the wave function information, you can calculate everything else about it-such as the object's magnetism, its conductivity and its likelihood to emit or absorb light."
"While the wave function is a mathematical expression and not a physical object, the team's method can reveal the behavior that the wave function describes: the probabilities that a quantum system will behave in one way versus another. In the world of quantum mechanics, probability is everything," reported by Phys.
Quantum mechanics dictate that before electrons can be measured with their positions, they do not have a definite location. Contrary to other models of the atom, an electron does not move in orbits like planets orbit the sun. Electrons move as waves, thus, they cannot be in a definite location.
"It's not totally obvious where it will be used, but it's a new technique that offers new opportunities," he said. "We've been using an optical lattice to capture atoms for years, and now it's become a new kind of measurement tool."
