PRESS-NEWS.org - Press Release Distribution
PRESS RELEASES DISTRIBUTION

Decay used to construct quantum information

2013-11-25
(Press-News.org) Contact information: Gertie Skaarup
skaarup@nbi.dk
45-35-32-53-20
University of Copenhagen - Niels Bohr Institute
Decay used to construct quantum information

Usually, when researchers work with quantum information, they do everything they can to prevent the information from decaying. Now researchers at the Niels Bohr Institute, among others, have flipped things around and are exploiting the decay to create the so-called entanglement of atomic systems, which is the foundation for quantum information processing. The results are published in the scientific journal, Nature.

"When working with quantum information, you would normally seek to isolate the system from the environment in order to not get a disturbing interaction that can destroy the fragile quantum state. But this is very difficult to avoid completely. So we thought that you could perhaps take the opposite approach and instead of seeing decay as the enemy, look at it as a friend and take advantage of it," explains Anders Søndberg Sørensen, a professor of quantum optics at the Niels Bohr Institute at the University of Copenhagen.

Electrons leaping hither and thither

The problem is that the quantum system is affected by the environment and exchanges energy with it. The electrons in the atoms jump from one energy state to another and researchers consider this kind of jump to be decay, because the information stored in the electrons disappears into its surroundings.

"But with our method we let the quantum system 'talk' with its surroundings and create a control of the electrons' jumps so that they are precisely in the state we want them to be in, and in that way we make use of the interaction with the environment," explains PhD student Florentin Reiter, who developed the theoretical model for the method together with Anders Sørensen.

The research is a collaboration with the experimental research group lead by David Wineland (recipient of the Nobel Prize in physics last year) at the National Institute for Standards and Technology in Boulder Colorado, USA.

Kicking the electrons into place

The method is based on a chain of ions comprised of magnesium and beryllium. They are cooled down to near absolute zero at minus 273 degrees C. The magnesium atoms are just there as a kind of cooling element in the chain of ions, while the beryllium atoms are the active elements. Entanglement is created between the electrons of the beryllium ions using carefully controlled laser light.

"The trick lies in the combination of laser light," explains Florentin Reiter and continues "the electrons can be in four energy states and if they jump around and land in a 'wrong' state, they are simply 'kicked' by the laser and we continue until they are where they are supposed to be. In that way there is perfect entanglement. Unlike in the past, when you had to use carefully designed laser pulses to create entanglement, researchers can now just turn on the laser and grab a cup of coffee and when they come back the electrons are in the correct state."

Up until this point, the decay of quantum information has been the biggest obstacle to making a quantum computer. The new experiment is the first time the problem has been turned on its head and the decay has been used constructively in a quantum computer. The researchers hope that this might be a way to overcome some of the problems that have previously made it difficult to make quantum computers. The researchers are now working to make more advanced quantum information processors based on the same ideas. In particular, they hope that similar techniques can be used to correct errors in a quantum computer.



INFORMATION:



For more information contact:

Anders Søndberg Sørensen
Professor, Quantum Optics
Niels Bohr Institute
University of Copenhagen
+45 3532-5240
+45 2466-1377
anders.sorensen@nbi.dk

Florentin Reiter
PhD student
Quantum Optics
Niels Bohr Institute
University of Copenhagen
0046-7232-70262
reiter@nbi.dk



ELSE PRESS RELEASES FROM THIS DATE:

Diamond 'flaws' pave way for nanoscale MRI

2013-11-25
Diamond 'flaws' pave way for nanoscale MRI By exploiting flaws in miniscule diamond fragments, researchers say they have achieved enough coherence of the magnetic moment inherent in these defects to harness their potential for precise quantum sensors in a ...

NIST demonstrates how losing information can benefit quantum computing

2013-11-25
NIST demonstrates how losing information can benefit quantum computing BOULDER, Colo -- Suggesting that quantum computers might benefit from losing some data, physicists at the National Institute of Standards and Technology (NIST) have entangled—linked ...

How living cells solved a needle in a haystack problem to produce electrical signals

2013-11-25
How living cells solved a needle in a haystack problem to produce electrical signals Filtered from a vast sodium sea, more than 1 million calcium ions per second gush through our cells' pores to generate charges Scientists have figured out how calcium channels – the infinitesimal ...

New genomic study provides a glimpse of how whales could adapt to ocean

2013-11-25
New genomic study provides a glimpse of how whales could adapt to ocean The latest study was published online in Nature Genetics November 24, 2013, Shenzhen, China - In a paper published in Nature Genetics, researchers from Korea Institute of Ocean Science and Technology, Korea Genome Research ...

Scientists prove X-ray laser can solve protein structures from scratch

2013-11-25
Scientists prove X-ray laser can solve protein structures from scratch SLAC's linac coherent light source reaches key milestone in decoding biological structures that were out of reach A study shows for the first time that X-ray lasers can ...

X-rays reveal another feature of high-temperature superconductivity

2013-11-25
X-rays reveal another feature of high-temperature superconductivity Discovery of a giant resonance puts these materials further apart Classical and high-temperature superconductors differ hugely in the value of the critical temperatures at which ...

UNL scientists develop novel X-ray device

2013-11-25
UNL scientists develop novel X-ray device Research quality X-rays could have widespread applications Lincoln, Neb., Nov. 24 – Using a compact but powerful laser, a research team at the University of Nebraska-Lincoln has developed a new way to generate ...

Unusual greenhouse gases may have raised ancient Martian temperature

2013-11-25
Unusual greenhouse gases may have raised ancient Martian temperature Much like the Grand Canyon, Nanedi Valles snakes across the Martian surface suggesting that liquid water once crossed the landscape, according to a team of researchers who believe that molecular hydrogen ...

Study identifies protein essential for immune recognition, response to viral infection

2013-11-25
Study identifies protein essential for immune recognition, response to viral infection Mice lacking GEF-H1 protein expression unable to mount immune defense against influenza A Massachusetts General Hospital (MGH)-led research team has identified an immune ...

Even if emissions stop, carbon dioxide could warm Earth for centuries

2013-11-25
Even if emissions stop, carbon dioxide could warm Earth for centuries Even if carbon dioxide emissions came to a sudden halt, the carbon dioxide already in Earth's atmosphere could continue to warm our planet for hundreds of years, according to Princeton University-led ...

LAST 30 PRESS RELEASES:

Adults 65 years and older not immune to the opioid epidemic, new study finds

Artificial intelligence emerging as powerful patient safety tool in pediatric anesthesia

Mother’s ZIP code, lack of access to prenatal care can negatively impact baby’s health at birth, new studies show

American Society of Anesthesiologists honors John M. Zerwas, M.D., FASA, with Distinguished Service Award

A centimeter-scale quadruped piezoelectric robot with high integration and strong robustness

Study confirms that people with ADHD can be more creative. The reason may be that they let their mind wander

Research gives insight into effect of neurodegenerative diseases on speech rhythm

Biochar and plants join forces to clean up polluted soils and boost ecosystem recovery

Salk scientist Joseph Ecker awarded McClintock Prize for Plant Genetics and Genome Studies

ADHD: Women are diagnosed five years later than men, despite symptoms appearing at the same age.

Power plants may emit more pollution during government shutdowns

Increasing pressures for conformity de-skilling and demotivating teachers, study warns

Researchers develop smarter menstrual product with potential for wearable health monitoring

Microwaves for energy-efficient chemical reactions

MXene current collectors could reduce size, improve recyclability of Li-ion batteries

Living near toxic sites linked to aggressive breast cancer

New discovery could open door to male birth control

Wirth elected Fellow of American Physical Society

The Journal of Nuclear Medicine Ahead-of-Print Tip Sheet: October 10, 2025

Destined to melt

Attitudes, not income, drive energy savings at home

The playbook for perfect polaritons

‘Disease in a dish’ study of progressive MS finds critical role for unusual type of brain cell

Solar-powered method lights the way to a ‘de-fossilized’ chemical industry

Screen time linked to lower academic achievement among Ontario elementary students

One-year outcomes after traumatic brain injury and early extracranial surgery in the TRACK-TBI Study

Enduring outcomes of COVID-19 work absences on the US labor market

Affirmative action repeal and racial and ethnic diversity in us medical school admissions

Cancer progression illuminated by new multi-omics tool

Screen time and standardized academic achievement tests in elementary school

[Press-News.org] Decay used to construct quantum information