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 shield’ placed in the nose may soon treat common hay fever trigger

Beetles under climate stress lay larger male eggs: Wolbachia infection drives adaptive reproduction strategy in response to rising temperature and CO₂

Groundbreaking quantum study puts wave-particle duality to work

Weekly injection could be life changing for Parkinson’s patients

Toxic metals linked to impaired growth in infants in Guatemala

Being consistently physically active in adulthood linked to 30–40% lower risk of death

Nerve pain drug gabapentin linked to increased dementia, cognitive impairment risks

Children’s social care involvement common to nearly third of UK mums who died during perinatal period

‘Support, not judgement’: Study explores links between children’s social care involvement and maternal deaths

Ethnic minority and poorer children more likely to die in intensive care

Major progress in fertility preservation after treatment for cancer of the lymphatic system

Fewer complications after additional ultrasound in pregnant women who feel less fetal movement

Environmental impact of common pesticides seriously underestimated

The Milky Way could be teeming with more satellite galaxies than previously thought

New study reveals surprising reproductive secrets of a cricket-hunting parasitoid fly

Media Tip Sheet: Symposia at ESA2025

NSF CAREER Award will power UVA engineer’s research to improve drug purification

Tiny parasitoid flies show how early-life competition shapes adult success

New coating for glass promises energy-saving windows

Green spaces boost children’s cognitive skills and strengthen family well-being

Ancient trees dying faster than expected in Eastern Oregon

Study findings help hone precision of proven CVD risk tool

Most patients with advanced melanoma who received pre-surgical immunotherapy remain alive and disease free four years later

Introducing BioEmu: A generative AI Model that enables high-speed and accurate prediction of protein structural ensembles

Replacing mutated microglia with healthy microglia halts progression of genetic neurological disease in mice and humans

New research shows how tropical plants manage rival insect tenants by giving them separate ‘flats’

Condo-style living helps keep the peace inside these ant plants

Climate change action could dramatically limit rising UK heatwave deaths

Annual heat-related deaths projected to increase significantly due to climate and population change

Researchers discover new way cells protect themselves from damage

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