Researchers in University of Vienna and MIT have used lasers to levitate and cool a glass nanoparticle into the quantum regime. Although it is trapped in a room-temperature environment, the particle’s motion is solely governed by the laws of quantum physics.
Quantum properties of individual atoms can be controlled and manipulated with laser light. Even hundreds of millions of atoms can be pushed into macroscopic quantum states of matter such as quantum gas or Bose-Einstein condensate, which today are also widely used in quantum technologies. An exciting next step is to extend this level of quantum control to solid-state objects whose the density is a billion times higher.
The researchers chose to experiment with a glass bead approximately 1000 times smaller than a grain of sand and containing a few hundred million atoms.
The scientists had to isolate the solid from influences of the environment and to remove all thermal energy by cooling it down to temperatures very close to absolute zero (-273.15 degrees Celsius) so that quantum mechanics dominates the particle’s motion.
The team has been working on implementing a laser-cooling method.
The surface of the glass bead is extremely hot, around 300 degrees Celsius, because the laser heats up the electrons in the material. But the motion of the center of mass of the particle is ultra-cold, around 0.00001 degrees Celsius away from absolute zero. But the hot particle moves in a quantum way.
The paper has been published in Science. (Phys.org)