Sign In

Communications of the ACM

ACM TechNews

Nature: Electronic Read-Out of Quantum Bits

TbPc2 molecule

TbPc2 molecule quantum-bit device. Electrons (red) from the electrodes jump onto the molecule reading out the electronic spin (orange) and the nuclear spin (green).

Credit: C. Grupe, KIT

Magnetic molecule complexes may solve a dilemma for quantum computing, which would use quantum effects and also would be susceptible to external influences.

The quantum state must be kept stable and shielded, while the information must be read out in a controlled manner for further use, says Karlsruhe Institute of Technology (KIT) professor Mario Ruben. Researchers from KIT and partners from Grenoble and Strasbourg have read out the quantum state of an atom directly by using electrodes. Their study is based on terbium, a metal atom with a pronounced magnetic moment, a spin, surrounded by organic molecules that shield the atom. "When synthesizing this protective enclosure, we can exactly define how much the metal atom sees of the outer world," Ruben says.

The molecule was exposed to various changing magnetic fields and the jump of the spin was reflected by the amplitude of the current curve. "By measuring current flow, we found that the nuclear spin of the metal atom is stable for up to 20 seconds," which is a very long time for quantum mechanical processes, Ruben notes.

Ruben says the research will be key for spintronics and quantum computing.

From Karlsruhe Institute of Technology 
View Full Article

Abstracts Copyright © 2012 Information Inc., Bethesda, Maryland, USA 


No entries found

Sign In for Full Access
» Forgot Password? » Create an ACM Web Account