Major discovery in controlling quantum states of single atoms

February 16, 2018, Institute for Basic Science
Major discovery in controlling quantum states of single atoms
The metallic tip of a scanning tunneling microscope is used to drive the magnetic quantum state of an iron atom into a different direction. Credit: Institute for Basic Science (IBS)

Researchers at the Center for Quantum Nanoscience within the Institute for Basic Science (IBS) have made a major breakthrough in controlling the quantum properties of single atoms. In an international collaboration with IBM Research in San Jose, California, using advanced techniques, the scientists identified which mechanisms destroy the quantum properties of individual atoms by manipulating the magnetic state of a single iron atom on a thin insulator. Using a scanning tunneling microscope with an atomically sharp metal tip, they were able to image individual iron atoms and measure and control the time that they maintain their quantum behavior.

Their findings, published in the journal Science Advances, show that the loss in quantum state superposition is mainly caused by nearby electrons that the researchers precisely injected into the iron atom.

"We found that almost every electron destroys the ," explains Dr. Philip Willke, first author of the study. "In addition, we found that nearby fluctuating magnets had a similar negative impact. While our experiments decreased the state of superposition on purpose, it also gave us valuable clues on how to improve the atoms' quantum states."

Andreas Heinrich, Director of the IBS Center for Quantum Nanoscience, said, "Understanding these destructive interactions allows us to avoid them in future experiments and improve the performance of magnetic quantum sensors that, in this case, only consist of a single atom."

Quantum nanoscience relies on harnessing the properties of atoms and molecules for potential advances in quantum sensing, potentially improving devices using such technology, including hospital MRI machines.

Quantum computers could also potentially benefit from this research. While still in early development, quantum computation promises to outperform classical computers in tasks such as database management, search and optimization. A quantum system can maintain two quantum states simultaneously, a condition known as the superposition of quantum states. However, when such a system interacts in particular environments—either through desired or undesired contact—this superposition of is easily destroyed. Physicists seek to understand and control these processes.

Explore further: A new kind of quantum computer

More information: "Probing quantum coherence in single-atom electron spin resonance" Science Advances (2018). DOI: 10.1126/sciadv.aaq1543 , http://advances.sciencemag.org/content/4/2/eaaq1543

Related Stories

A new kind of quantum computer

November 6, 2017

Quantum mechanics incorporates some very non-intuitive properties of matter. Quantum superposition, for example, allows an atom to be simultaneously in two different states with its spin axis pointed both up and down, or ...

Experimental method measures robustness of quantum coherence

July 27, 2017

Researchers at the UAB have come up with a method to measure the strength of the superposition coherence in any given quantum state. The method, published in the journal Proceedings of the Royal Society A, is based on the ...

Turning ions into quantum cats

September 29, 2017

In Schrödinger's famous thought experiment, a cat seems to be both dead and alive—an idea that strains credulity. These days, cats still don't act this way, but physicists now regularly create analogues of Schrödinger's ...

Scientists realize quantum bit with a bent nanotube

July 29, 2013

One of the biggest challenges in quantum science is to build a functioning quantum bit, the basic element for the quantum computer. An important theoretical candidate for such a quantum bit is using a bent carbon nanotube. ...

Controlling quantum states atom by atom

June 9, 2016

An international consortium led by researchers at the University of Basel has developed a method to precisely alter the quantum mechanical states of electrons within an array of quantum boxes. The method can be used to investigate ...

Recommended for you

Pond dwellers called Euglena swim in polygons to avoid light

September 25, 2018

In any seemingly quiet pond the still waters actually teem with tiny pond dwellers called Euglena gracilis. Unseen to the naked eye, the single-celled organism spirals through the water, pulled along a relatively straight ...

Explainer: The US push to boost 'quantum computing'

September 24, 2018

A race by U.S. tech companies to build a new generation of powerful "quantum computers" could get a $1.3 billion boost from Congress, fueled in part by lawmakers' fear of growing competition from China.

A new way to count qubits

September 24, 2018

Researchers at Syracuse University, working with collaborators at the University of Wisconsin (UW)-Madison, have developed a new technique for measuring the state of quantum bits, or qubits, in a quantum computer.

0 comments

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.