Topological superconductor phase may solve decoherence problem in quantum computers

March 9, 2018 by Bob Yirka, Phys.org report
Credit: CC0 Public Domain

A team of researchers from Japan, the U.S. and China, has identified a topological superconducting phase for possible use in an iron-based material in quantum computers. In their paper published in the journal Science, the team outlines their study of the phase, which, they claim, shows promise as a means for solving the decoherence problem in quantum computers.

As research surrounding quantum computers continues confront a number of problems. One is the tendency of quantum states to degrade, resulting in computing errors—a problem known as decoherence. Experts suggest that the solution to the problem is to develop a material capable of protecting the quantum state by employing just the right topological properties. In this way, localized noise would not be able to disturb the quantum state. In this new effort, the researchers report on the identification of a topological superconducting phase that they believe could satisfy this requirement.

The researchers report that they were able to attain three key kinds of measurements believed to be necessary for analyzing the of Fe(Te, Se) in sufficient detail, which they claim shows that the phase could prove suitable for protecting the in a system. They further report that the phase, once integrated into a suitable material, would be capable of supporting Majorana bound states (MBSs), which are quasiparticles so-named due to their discovery by Ettore Majorana. Prior research has suggested that a material capable of using Majorana properties might play a role in solving the decoherence problem.

The researchers note also that they were able to identify the helical spin polarization of the surface state and to measure the superconducting gap. They were also able to identify the . Taken together, the results of their testing indicate that MBSs could be induced in a material by exerting a magnetic field to the Fe(Te, Se). If their predictions pan out, the new phase could wind up as part of the next generation of quantum computers, possibly paving the way for machines capable of manipulating more qubits than those currently in use.

Explore further: Unconventional superconductor may be used to create quantum computers of the future

More information: Peng Zhang et al. Observation of topological superconductivity on the surface of an iron-based superconductor, Science (2018). DOI: 10.1126/science.aan4596 , science.sciencemag.org/content … 3/07/science.aan4596

Abstract
Topological superconductors are predicted to host exotic Majorana states that obey non-Abelian statistics and can be used to implement a topological quantum computer. Most of the proposed topological superconductors are realized in difficult-to-fabricate heterostructures at very low temperatures. Here by using high-resolution spin-resolved and angle-resolved photoelectron spectroscopy, we find that the iron-based superconductor FeTe1-xSex (x = 0.45, superconducting transition temperature Tc = 14.5 K) hosts Dirac-cone type spin-helical surface states at Fermi level; the surface states exhibit an s-wave superconducting gap below Tc. Our study shows that the surface states of FeTe0.55Se0.45 are 2D topologically superconducting, providing a simple and possibly high temperature platform for realizing Majorana states.

Related Stories

Spin-polarized surface states in superconductors

October 26, 2017

When it comes to entirely new, faster, more powerful computers, Majorana fermions may be the answer. These hypothetical particles can do a better job than conventional quantum bits (qubits) of light or matter. Why? Because ...

What's the noise eating quantum bits?

January 8, 2018

Super powerful quantum computing relies on quantum bits, aka qubits, which are the equivalent of the classical bits used in today's computers. SQUIDs are being investigated for the development of qubits. However, system noise ...

Recommended for you

Researchers study interactions in molecules using AI

October 19, 2018

Researchers from the University of Luxembourg, Technische Universität Berlin, and the Fritz Haber Institute of the Max Planck Society have combined machine learning and quantum mechanics to predict the dynamics and atomic ...

Pushing the extra cold frontiers of superconducting science

October 18, 2018

Measuring the properties of superconducting materials in magnetic fields at close to absolute zero temperatures is difficult, but necessary to understand their quantum properties. How cold? Lower than 0.05 Kelvin (-272°C).

The big problem of small data: A new approach

October 18, 2018

Big Data is all the rage today, but Small Data matters too! Drawing reliable conclusions from small datasets, like those from clinical trials for rare diseases or in studies of endangered species, remains one of the trickiest ...

2 comments

Adjust slider to filter visible comments by rank

Display comments: newest first

poisonoak
3.7 / 5 (3) Mar 11, 2018
Increasing disturbing trend at phys.org and other web sites - tacking on a picture, any picture, that has nothing to do with the subject at hand. See https://phys.org/...cs.html. Same stupid picture having nothing to do with the article.
DonGateley
3 / 5 (2) Mar 11, 2018
@jd_ If you are registered at phys.org and are logged in then you can select "Ignore User" under a post and never see anything from mackita and the other schizo kook fools that love to shit their ignorance all over physics comment sections. I wouldn't bother looking at the comments without that facility. Over time you will find that there are only a handful of real contributors but they make it worthwhile.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.