Physicists Cross Hurdle in Quantum Manipulation of Matter
ScienceDaily (Sep. 17, 2010) — Finding ways to control matter at the level of single atoms and electrons fascinates many scientists and engineers because the ability to manipulate single charges and single magnetic moments (spins) may help researchers penetrate deep into the mysteries of quantum mechanics and modern solid-state physics. It may also allow development of new, highly sensitive magnetometers with nanometer resolution, single-spin transistors for coherent spintronics, and solid-state devices for quantum information processing.
A collaboration of experimentalists from the Kavli Institute of Nanosciences at Delft University of Technology and theorists at the US Department of Energy's Ames Laboratory made a breakthrough in the area of controlling single quantum spins. The researchers developed and implemented a special kind of quantum control over a single quantum magnetic moment (spin) of an atomic-sized impurity in diamond. (Credit: Image courtesy of DOE/Ames Laboratory)
Recently, a collaboration of experimentalists from the Kavli Institute of Nanosciences at Delft University of Technology and theorists at the U.S. Department of Energy's Ames Laboratory made a breakthrough in the area of controlling single quantum spins. The results were published in ScienceExpress on Sept. 9.
The researchers developed and implemented a special kind of quantum control over a single quantum magnetic moment (spin) of an atomic-sized impurity in diamond. These impurities, called nitrogen-vacancy (or N-V) centers, have attracted much attention due to their unusual magnetic and optical properties. But their fragile quantum states are easily destroyed by even miniscule interactions with the outside world.
...
Read more here/Leia mais aqui: Science Daily
+++++
Published Online September 9, 2010
Science DOI: 10.1126/science.1192739
Universal Dynamical Decoupling of a Single Solid-State Spin from a Spin
BathG. de Lange,1 Z. H. Wang,2 D. Ristè,1 V. V. Dobrovitski,2 R. Hanson1,*
Controlling the interaction of a single quantum system with its environment is a fundamental challenge in quantum science and technology. We dramatically suppress the coupling of a single spin in diamond with the surrounding spin bath by using double-axis dynamical decoupling. The coherence is preserved for arbitrary quantum states, as verified by quantum process tomography. The resulting coherence time enhancement is found to follow a general scaling with the number of decoupling pulses. No limit is observed for the decoupling action up to 136 pulses, for which the coherence time is enhanced more than 25 times compared to spin echo. These results uncover a new regime for experimental quantum science and allow to overcome a major hurdle for implementing quantum information protocols.
1 Kavli Institute of Nanoscience Delft, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands.
2 Ames Laboratory and Iowa State University, Ames, IA 50011, USA.
* To whom correspondence should be addressed. E-mail: r.hanson@tudelft.nl
Received for publication 24 May 2010. Accepted for publication 19 August 2010.
+++++
Professores, pesquisadores e alunos de universidades públicas e privadas com acesso ao site CAPES/Periódicos podem ler gratuitamente este artigo da Science e de mais 22.440 publicações científicas.
+++++
