Scientists at the Technical University of Delft have succeeded in the spin state of a single electron fully protect against environmental influences. Electron spins in solids are promising building blocks for quantum technologies such as a quantum computer, but the interaction of the spins with the environment was so far a major stumbling block.
With the spin of the electron with very short pulses to more hits, the researchers managed to undo this interaction. This spin behaves as if he is disconnected from its surroundings. They also prove that this technique works for every possible spin state, and thus applicable in a future quantum computer. The results are published online this week in the journal Science.
0 and 1 simultaneously
Quantum particles like an atom or an electron can be found in several states simultaneously. For example, the magnetic moment of an electron, the so-called 'spin', while having two different directions. If the spin is used in a computer, it is simultaneously 0 and 1, and not just 0 or 1 as in an ordinary computer circuitry. This makes possible high-speed computing. To build such a quantum computer is greatly hindered by the environment - also consisting of quantum particles - the state of the spin disturbs.
The Delft team with electrons in diamond, a favorite material for quantum scientists.The uniqueness of diamond is that the quantum properties even at room temperature visible. This is a great advantage for future applications. The researchers were already managed to spin of a single electron and measure the ambient environment mapping. By using high frequency pulses of only a few nano seconds, the Delft team has now managed to spin a single electron to check with a world record accuracy.This enabled the researchers for the first time the spider protect the environment, a breakthrough result.
The researchers turned the spider very carefully at regular intervals, so the effect of the environment was averaged and it seemed to spin completely isolated. The more they spin omklapten, the longer the quantum state remained. Protection for 130 pulses was more than 25 times longer than previously measured. They finally showed that the protection works for every possible quantum state. These results are a major breakthrough in quantum science, where the environmental influences to date have been the biggest stumbling block for new fundamental experiments and applications in quantum technologies.
The study took place at the Kavli Institute of Nanoscience Delft University of Technology and was led by Ronald Hanson (FOM project manager). The work is theoretically supported by colleagues at Ames Laboratory in the United States. Gijs de Lange first author is a PhD student employed by NWO. The research was conducted with a grant from the Foundation FOM, NWO and DARPA. Ronald Hanson, a member of the Young Academy of the Academy, in 2007 received a NWO-Vidi grant for research on quantum information in diamond.