"This gives us an unprecedented tool to control a quantum system, perhaps even atom by atom," said Patil, lead author of the paper. But as the imaging beam was made brighter and measurements made more frequently, the tunneling reduced dramatically. When the imaging laser was off, or turned on only dimly, the atoms tunneled freely. A light microscope can't see individual atoms, but the imaging laser causes them to fluoresce, and the microscope captured the flashes of light. The researchers observed the atoms under a microscope by illuminating them with a separate imaging laser. Using this tuning, we've also been able to demonstrate an effect called 'emergent classicality' in this quantum system." Quantum effects fade, and atoms begin to behave as expected under classical physics. "Also, due to the high degree of control we've been able to demonstrate in our experiments, we can gradually 'tune' the manner in which we observe these atoms. "This is the first observation of the Quantum Zeno effect by real space measurement of atomic motion," Vengalattore said. Previous experiments have demonstrated the Zeno Effect with the "spins" of subatomic particles. George Sudarshan and Baidyanath Misra at the University of Texas, Austin, who pointed out that the weird nature of quantum measurements allows, in principle, for a quantum system to be "frozen" by repeated measurements. This so-called "Quantum Zeno effect", named for a Greek philosopher, derives from a proposal in 1977 by E. The researchers demonstrated that they were able to suppress quantum tunneling merely by observing the atoms. Under extreme cold velocity is almost zero, so there is a lot of flexibility in position when you observe them, atoms are as likely to be in one place in the lattice as another. Temperature is a measure of a particle's motion. The famous Heisenberg uncertainty principle says that the position and velocity of a particle interact. In that state the atoms arrange in an orderly lattice just as they would in a crystalline solid.,But at such low temperatures, the atoms can "tunnel" from place to place in the lattice. Chakram created and cooled a gas of about a billion Rubidium atoms inside a vacuum chamber and suspended the mass between laser beams. Graduate students Yogesh Patil and Srivatsan K. 2 issue of the journal Physical Review Letters The experiments were performed in the Utracold Lab of Mukund Vengalattore, assistant professor of physics, who has established Cornell's first program to study the physics of materials cooled to temperatures as low as.
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