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

A superconductor-surrogate earns its stripes

Berkeley Lab study reveals origins of an exotic phase of matter

2013-11-19
(Press-News.org) Contact information: Alison Hatt
ajhatt@lbl.gov
510-486-7154
DOE/Lawrence Berkeley National Laboratory
A superconductor-surrogate earns its stripes Berkeley Lab study reveals origins of an exotic phase of matter

Understanding superconductivity – whereby certain materials can conduct electricity without any loss of energy – has proved to be one of the most persistent problems in modern physics. Scientists have struggled for decades to develop a cohesive theory of superconductivity, largely spurred by the game-changing prospect of creating a superconductor that works at room temperature, but it has proved to be a tremendous tangle of complex physics.

Now scientists at the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have teased out another important tangle from this giant ball of string, bringing us a significant step closer to understanding how high- temperature superconductors work their magic. Working with a model compound, the team illuminated the origins of the so-called "stripe phase" in which electrons become concentrated in stripes throughout a material, and which appears to be linked to superconductivity.

"We're trying to understand nanoscale order and how that determines material properties such as superconductivity," said Robert Kaindl, a physicist in Berkeley Lab's Materials Sciences Division. "Using ultrafast optical techniques, we are able to observe how charge stripes start to form on a time scale of hundreds of femtoseconds." A femtosecond is just one millionth of one billionth of a second.

Electrons in a solid material interact extremely quickly and on very short length scales, so to observe their behavior researchers have built extraordinarily powerful "microscopes" that zoom into fast events using short flashes of laser light. Kaindl and his team brought to bear the power of their ultrafast-optics expertise to understand the stripe phase in strontium-doped lanthanum nickelate (LSNO), a close cousin of high-temperature superconducting materials.

"We chose to work with LSNO because it has essential similarities to the cuprates (an important class of high-temperature superconductors), but its lack of superconductivity lets us focus on understanding just the stripe phase," said Giacomo Coslovich, a postdoctoral researcher at Berkeley Lab working with Kaindl.

"With science, you have to simplify your problems," Coslovich continued. "If you try to solve them all at once with their complicated interplay, you will never understand what's going on."

Kaindl and Coslovich are corresponding authors on a paper reporting these results in Nature Communications, titled, "Ultrafast charge localization in a stripe-phase nickelate." Coauthoring the paper are Bernhard Huber, Yi Zhu, Yi-De Chuang, Zahid Hussain, Hans Bechtel, Michael Martin and Robert Schoenlein of Berkeley Lab, along with Wei-Sheng Lee, and Zhi-Xun Shen of SLAC National Accelerator Laboratory, and Takao Sasagawa of Tokyo Institute of Technology.

Stripes are seen in all high-temperature superconductors near the superconducting transition temperature. In this LSNO crystal stripes form only at cryogenic temperatures of about 168 degrees Celsius (approximately 271 °F), yet at far higher temperatures the team hit upon large changes of the material's infrared reflectivity. These invisible "color" changes represent an energy threshold for electrical currents, dubbed the energetic "pseudogap", which grows as the crystal cools – revealing a progressive localization of charges around the nickel atoms.

The scientists then examined the dynamics of LSNO in "pump-probe" experiments, where they melted stripes with an initial ultrafast pulse of laser light and measured the optical changes with a second, delayed pulse. This allowed them to map out the early steps of charge ordering, exposing surprisingly fast localization dynamics preceding the development of organized stripe patterns. A final twist came when they probed the vibrations between nickel and oxygen atoms, uncovering a remarkably strong coupling to the localized electrons with synchronous dynamics.

Beyond the ultrafast measurements, the team also studied X-ray scattering and the infrared reflectance of the material at the neighboring Advanced Light Source, to develop a thorough, cohesive understanding of the stripe phase and why it forms.

Said Kaindl, "We took advantage of our fortunate location in the national lab environment, where we have both these ultrafast techniques and the Advanced Light Source. This collaborative effort made this work possible."

Having illuminated the origins of the stripe phase in LSNO, the researchers expect their results to provide new impetus to understanding the "pseudogap" in other correlated oxides – especially in high-temperature superconductors where fluctuating stripes occur while their role for the superconductivity mechanism remains unclear.



INFORMATION:

This research was supported by the U.S. Department of Energy, Office of Science.

Additional Information:

For more on the Ultrafast Materials program at Berkeley Lab, visit http://www.lbl.gov/msd

Lawrence Berkeley National Laboratory addresses the world's most urgent scientific challenges by advancing sustainable energy, protecting human health, creating new materials, and revealing the origin and fate of the universe. Founded in 1931, Berkeley Lab's scientific expertise has been recognized with 13 Nobel prizes. The University of California manages Berkeley Lab for the U.S. Department of Energy's Office of Science. For more, visit http://www.lbl.gov.

The Advanced Light Source is a third-generation synchrotron light source producing light in the x-ray region of the spectrum that is a billion times brighter than the sun. A DOE national user facility, the ALS attracts scientists from around the world and supports its users in doing outstanding science in a safe environment. For more information visit www-als.lbl.gov.

The DOE Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time. For more information, please visit science.energy.gov.



ELSE PRESS RELEASES FROM THIS DATE:

Like other offenses, cyberdeviance and cybercrime seem to start and peak in the teen years

2013-11-19
Like other offenses, cyberdeviance and cybercrime seem to start and peak in the teen years Tech-y teens, often more curious than criminal, are likely to start turning their talents to cyberdeviance and cybercrime at about age 15, with such activities peaking ...

Princeton-Harvard study finds Harlem charter school students more likely to attend college

2013-11-19
Princeton-Harvard study finds Harlem charter school students more likely to attend college All male students stayed out of jail, female students were 71 percent less likely to become teen moms PRINCETON, ...

Special issue of Gut Microbes on Helicobacter pylori

2013-11-19
Special issue of Gut Microbes on Helicobacter pylori A special issue on Helicobacter pylori has been published by Landes Bioscience (Austin, TX USA). The articles contained in this special issue of the journal Gut Microbes have been authored by world-class investigators ...

Study finds similar outcomes for repair or replacement of damaged heart valves

2013-11-19
Study finds similar outcomes for repair or replacement of damaged heart valves Penn Medicine-led research provides first rigorous comparison of two surgical approaches for severe heart valve disease DALLAS – New research presented ...

Global warming in the Canadian Arctic

2013-11-19
Global warming in the Canadian Arctic Thaw ponds: An unaccounted source of greenhouse gas Québec City, November 18, 2013 – Ph.D. student Karita Negandhi and professor Isabelle Laurion from INRS'Eau Terre Environnement Research Centre, in collaboration with other Canadian, ...

Optimizing electronic correlations for superconductivity

2013-11-19
Optimizing electronic correlations for superconductivity The decadeslong effort to create practical superconductors moved a step forward with the discovery at Rice University that two distinctly different iron-based compounds share common mechanisms for moving electrons. Samples ...

Staying on medication may not translate to avoiding readmission

2013-11-19
Staying on medication may not translate to avoiding readmission DURHAM, N.C. – A targeted effort to help high-risk heart failure patients stay on their medications did improve adherence to drug regimens, but had surprisingly little effect lowering hospital ...

Avoiding poisons: A matter of bitter taste

2013-11-19
Avoiding poisons: A matter of bitter taste Recent highlights in the journal Molecular Biology and Evolution In most animals, taste has evolved to avoid all things bitter---a key to survival--- to avoid eating something that could ...

The big male nose

2013-11-19
The big male nose University of Iowa study explains why men's noses are bigger than women's Human noses come in all shapes and sizes. But one feature seems to hold true: Men's noses are bigger than women's. A new study from the University of Iowa concludes ...

Pressure cooking to improve electric car batteries

2013-11-19
Pressure cooking to improve electric car batteries By creating nanoparticles with controlled shape, engineers believe smaller, more powerful and energy efficient batteries can be built RIVERSIDE, Calif. (http://www.ucr.edu) — Batteries that power electric ...

LAST 30 PRESS RELEASES:

Molecular stool test could improve detection of tuberculosis in adults with HIV

Suspected fibrocartilaginous embolus in Asian small-clawed otter (Aonyx cinereus)

Enhancing heat transfer using the turbulent flow of viscoelastic fluids

Exercise as an anti-ageing intervention to avoid detrimental impact of mental fatigue

UMass Amherst Nursing Professor Emerita honored as ‘Living Legend’

New guidelines aim to improve cystic fibrosis screening

Picky eaters by day, buffet by night: Butterfly, moth diets sync to plant aromas

Pennington Biomedical’s Dr. Leanne Redman honored with the E. V. McCollum Award from the American Society for Nutrition

CCNY physicists uncover electronic interactions mediated via spin waves

Researchers’ 3D-printing formula may transform future of foam

Nurture more important than nature for robotic hand

Drug-delivering aptamers target leukemia stem cells for one-two knockout punch

New study finds that over 95% of sponsored influencer posts on Twitter were not disclosed

New sea grant report helps great lakes fish farmers navigate aquaculture regulations

Strain “trick” improves perovskite solar cells’ efficiency

How GPS helps older drivers stay on the roads

Estrogen and progesterone stimulate the body to make opioids

Dancing with the cells – how acoustically levitating a diamond led to a breakthrough in biotech automation

Machine learning helps construct an evolutionary timeline of bacteria

Cellular regulator of mRNA vaccine revealed... offering new therapeutic options

Animal behavioral diversity at risk in the face of declining biodiversity

Finding their way: GPS ignites independence in older adult drivers

Antibiotic resistance among key bacterial species plateaus over time

‘Some insects are declining but what’s happening to the other 99%?’

Powerful new software platform could reshape biomedical research by making data analysis more accessible

Revealing capillaries and cells in living organs with ultrasound

American College of Physicians awards $260,000 in grants to address equity challenges in obesity care

Researchers from MARE ULisboa discover that the European catfish, an invasive species in Portugal, has a prolonged breeding season, enhancing its invasive potential

Rakesh K. Jain, PhD, FAACR, honored with the 2025 AACR Award for Lifetime Achievement in Cancer Research

Solar cells made of moon dust could power future space exploration

[Press-News.org] A superconductor-surrogate earns its stripes
Berkeley Lab study reveals origins of an exotic phase of matter