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Elusive half-quantum vortices in a superfluid

Gained understanding in quantum physics may be a step towards quantum computers

Date:
December 14, 2016
Source:
Aalto University
Summary:
Researchers have discovered half-quantum vortices in superfluid helium. This vortex is a topological defect, exhibited in superfluids and superconductors, which carries a fixed amount of circulating current. These objects originally predicted to exist in superfluid helium in 1976. The discovery will provide access to the cores of half-quantum vortices, hosting isolated Majorana modes, exotic solitary particles. Understanding these modes is essential for the progress of quantum information processing, building a quantum computer.
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Researchers in Aalto University, Finland, and P.L. Kapitza Institute in Moscow have discovered half-quantum vortices in superfluid helium. This vortex is a topological defect, exhibited in superfluids and superconductors, which carries a fixed amount of circulating current.

'This discovery of half-quantum vortices culminates a long search for these objects originally predicted to exist in superfluid helium in 1976,' says Samuli Autti, Doctoral Candidate at Aalto University in Finland.

'In the future, our discovery will provide access to the cores of half-quantum vortices, hosting isolated Majorana modes, exotic solitary particles. Understanding these modes is essential for the progress of quantum information processing, building a quantum computer,' Autti continues.

Macroscopic coherence in quantum systems such as superfluids and superconductors provides many possibilities, and some central limitations. For instance, the strength of circulating currents in these systems is limited to certain discrete values by the laws of quantum mechanics. A half-quantum vortex overcomes that limitation using the non-trivial topology of the underlying material, a topic directly related to the 2016 Nobel Prize in physics.

Among the emerging properties is one analogous to the so-called Alice string in high-energy physics, where a particle on a route around the string flips the sign of its charge. In general the quantum character of these systems is already utilized in ultra-sensitive SQUID amplifiers and other important quantum devices.


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Materials provided by Aalto University. Note: Content may be edited for style and length.


Journal Reference:

  1. S. Autti, V.V. Dmitriev, J.T. Mäkinen, A.A. Soldatov, G.E. Volovik, A.N. Yudin, V.V. Zavjalov, V.B. Eltsov. Observation of Half-Quantum Vortices in Topological Superfluid 3He. Physical Review Letters, 2016 DOI: 10.1103/PhysRevLett.117.255301

Cite This Page:

Aalto University. "Elusive half-quantum vortices in a superfluid: Gained understanding in quantum physics may be a step towards quantum computers." ScienceDaily. ScienceDaily, 14 December 2016. <www.sciencedaily.com/releases/2016/12/161214115119.htm>.
Aalto University. (2016, December 14). Elusive half-quantum vortices in a superfluid: Gained understanding in quantum physics may be a step towards quantum computers. ScienceDaily. Retrieved May 27, 2017 from www.sciencedaily.com/releases/2016/12/161214115119.htm
Aalto University. "Elusive half-quantum vortices in a superfluid: Gained understanding in quantum physics may be a step towards quantum computers." ScienceDaily. www.sciencedaily.com/releases/2016/12/161214115119.htm (accessed May 27, 2017).

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