Press release: One step closer to future quantum computers
2019-09-17
Physicists at Uppsala University have identified how to distinguish between true and ‘fake’ Majorana states in one of the most commonly used experimental setups, by means of supercurrent measurements. This theoretical study is a crucial step for advancing the field of topological superconductors and applications of Majorana states for robust quantum computers. New experiments testing this approach are expected next.
Majorana states exist as zero-energy states at the ends of topological superconductors (a special type of superconductors, materials that conduct with zero resistance when cooled close to absolute zero temperature), where low-energy states are robust against defects. Majorana states have exotic properties that make them promising candidates as qubits for fault-tolerant quantum computers. However, in experiments trivial zero-energy states mimicking Majorana states can also appear. The difficulty in telling apart the true and these ‘fake’ Majoranas is a problem that has hampered the experimental progress in this field of research and has been a thorn in the side of experts.
A solution to this problem has been proposed in a recent study by Annica Black-Schaffer’s group. The authors simulated the entire system of one of the most common experimental setups used in engineering topological superconductors as accurately as possible and captured the main effects of all the components. By investigating the supercurrent (the current in superconductors) between two engineered superconductors, they found that there is a sign reversal in the supercurrent due to the trivial ‘fake’ Majorana state under magnetic field application, whereas such sign reversal is not produced by true Majorana states. They then concluded that supercurrents offer a powerful tool for the unambiguous distinction between trivial states and topological Majorana states.
“This study helps and motivates experimentalists towards the proper identification of topological Majoranas by using supercurrent measurements. Our study shows that we need to carry out more exact modelling,” says Jorge Cayao, postdoctoral researcher at Uppsala University.
“It is crucial that we are certain that we have actually engineered Majorana states and not some trivial states. This study presents a way to accomplish that through supercurrent measurements,” says Oladunjoye Awoga, PhD student at Uppsala University.
Article
Oladunjoye A. Awoga, Jorge Cayao, Annica M. Black-Schaffer: Supercurrent Detection of Topologically Trivial Zero-Energy States in Nanowire Junctions; Physical Review Letters; Phys. Rev. Lett. 123, 117001 – Published 12 September 2019, https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.123.117001, https://doi.org/10.1103/PhysRevLett.123.117001,
Contact
Annica Black-Schaffer, Professor at Department of Physics and Astronomy, Uppsala University, Sweden, annica.black-schaffer@physics.uu.se, +46-(0) 76-795 06 49
Jorge Cayao, post doc at Department of Physics and Astronomy, Uppsala University, Sweden, jorge.cayao@physics.uu.se, +46 (0)76-555 04 83
Annica Black-Schaffer's group: http://materials-theory.physics.uu.se/blackschaffer/
More news
-
Available position: Nystartsjobb: Administrativ assistent
2021-01-21
-
Available position: PhD position in studying hydrogen in amorphous materials
2021-01-19
-
Available position: PhD student in Materials Theory for Quantum Control
2021-01-15
-
You did not miss the nuclide calendar, did you?
2020-12-14
-
Research Funding: ERC Consolidator Grant to Venkata Kamalakar Mutta
2020-12-09
-
Research Funding: 35 Million SEK in Grants for accessibility to infrastructure from the Swedish Research Council
2020-11-23
-
Infrastructure: Component testing for the EES facility can begin
2020-11-09
-
Research Funding: 35 Million SEK in Project and Starting Grants from the Swedish Research Council
2020-10-29
-
Education: The Bachelor Programme in Physics One of the Most Popular Programmes
2020-07-30
-
Educations Open for Late Application
2020-07-15
-
New World Ranking: Uppsala University Best in the Nordics in Physics
2020-07-14
-
Education: The Government’s Extra Investments – Uppsala University Gets This Many New Spots
2020-06-30
-
Press Release: New Form of Magnetic Order Discovered in the Element Neodymium
2020-05-29
-
Scholarships for current international students at Uppsala University academic year 2020/2021
2020-05-28
-
Education: Laboratory Exercises at a Distance
2020-05-11
-
Research: Unusual Type of Superconductivity Discovered
2020-04-07
-
Research: Magnetic Hydrogen-Based Superconductor Discovered
2020-02-26
-
Research: New Method to Simulate Vibrational Spectroscopy of Atoms
2020-02-26
-
Press Release: The University Invests 80 Million in Technology Environment for Advanced Research Equipment
2020-02-18
-
Let the ball swing at the Ångström Laboratory
2020-01-31
-
Collaboration: 3D-printing allows production of environmentally friendly radiation absorbers
2020-01-29
-
Press Release: Spin States can be Moved Faster than Expected
2020-01-23
-
Prize: Oscar Grånäs Awarded the Lindbomska belöningen
2020-01-20
-
Research: New Discovery Can Give Faster Spintronic Elements
2019-12-03
-
Welcome to the Nobel Lectures in Uppsala
2019-12-02
-
Research: Magnetic Currents in DNA-Molecules Understood with New Theory
2019-11-12
-
Welcome to 2019 inaugural lectures and the inauguration of professors ceremony
2019-11-01
-
Research Funding: 41 Million SEK in Project and Starting Grants from the Swedish Research Council
2019-10-31
-
New Honorary Doctors Appointed at Uppsala University
2019-10-16
-
Research Funding: ERC grants SEK 80 million to research on material theory
2019-10-14
-
Ulf Danielsson explains the Nobel Prize in Physics 2019
2019-10-08
-
Research: Superconducting material discovered with unique code
2019-10-04
-
Rajeev Ahuja APS Fellow 2019
2019-10-02
-
Research Funding: Project within Dynamic Quantum Matter is Granted 28 Millions
2019-10-01
-
Press release: High pressure electronic transitions a pathway to high-temperature superconductivity in hydrogen
2019-09-25
-
Press release: One step closer to future quantum computers
2019-09-17
-
Researcher Profile: “It’s OK to be driven by curiosity alone”
2019-05-10
-
Research: Ultrafast Transition to New Metastable Crystal Phase Discovered
2019-03-25
-
Research: New Particle World Record Key to the Mysteries of the Universe?
2019-02-27
-
Research: Our Universe: An expanding bubble in an extra dimension
2018-12-27
-
Press Release: Magnetic Antiparticles Offer New Horizons for Information Technologies
2018-08-15
-
Research: Neutrinos in the ice indicate source of cosmic rays
2018-07-12
-
Live Press Conference on Astrophysics Breakthrough
2018-07-12
-
Film: Why does the IceCube telescope measure neutrinos at the South Pole?
2018-07-12
-
Collaboration: New fund for PhD-students established
2018-06-04
-
Research: Magnetic Phase Transitions Become Faster
2018-04-16
-
Press release: New method enables high-resolution measurements of magnetism
2018-02-06
-
Research: Ultra Fast Change of Volume Discovered in Magnetic Materials
2018-01-26
-
Research Funding: Grants for renewable-energy research
2017-12-08
-
Research: On the hunt for new and peculiar superconductors
2017-10-27
-
Research: Measuring magnetism in 3D
2017-06-08
-
Collaboration: Seminar with Nobel Laureate Frank Wilczek "Time Crystals – New States of Matter"
2017-05-24
-
Press release: Magnetic order in a two-dimensional molecular chessboard
2017-05-22
-
Education: New study program for people newly arrived in Sweden
2017-02-22
-
Press release: A new type of nano-sensor detects DNA building blocks
2017-02-13
-
Uppsala’s FREIA Lab to help upgrade the Large Hadron Collider
2016-11-02
-
Press release from DLR: Comet lander Philea found
2016-09-05
-
Press release: Magnetism under the magnifying glass
2016-08-31
-
Article on New Scientist: Impossible vanishing stars could be signs of advanced alien life
2016-08-01
-
MAX IV – ready to open up a new world
2016-06-21
-
New combination of materials could speed up computers
2016-06-17
-
Collaborative project on thermal cameras in teaching
2016-06-16
-
Prize: Johan Larsson awarded Uppsala University's Pedagogical Prize 2016
2016-05-25
-
Press release: New method to create terahertz radiation advances materials science
2016-05-23
-
Campus movie about Ångström Laboratory
2015-11-13
-
90 million SEK from The Knut och Alice Wallenberg Foundation
2015-10-08
-
A colloquium on this year’s Nobel Prize in Physics
2015-10-06
-
Two independent and primitive envelopes of the bilobate nucleus of comet 67P
2015-09-29
-
Builds electronics to new experimental facility (in Swedish)
2015-06-12