Emergent resistance network suggests mechanism for colossal magnetoresistance
Scientists at Stanford University and RIKEN have revealed new clues on the microscopic processes by which resistance in certain materials is dramatically altered by the presence of magnetic fields.
Research by scientists at Stanford University and RIKEN has revealed new clues on the microscopic processes by which resistance in certain materials is dramatically altered by the presence of magnetic fields. Reported in Science, the discovery provides fundamental insights toward the development of radically new memory and switching devices.
Colossal magnetoresistance (CMR), a phenomenon in which enormous variations in resistance are produced by small magnetic field changes, has attracted attention as a means to develop low-power, more compact alternatives to conventional circuits. Unlike semiconductors such as silicon, electrons in the manganites and other transition metal oxides in which CMR occurs interact strongly with each other, held in place by a lattice that constrains their movement. CMR is triggered when a strong magnetic field induces such materials to tip from a charge-ordered insulating phase into a ferromagnetic metallic phase, drastically altering the material’s properties.
An earlier technique developed by the team was successful in producing manganite films only a few dozen nanometers thick capable of undergoing this transition from insulating to metallic phase. To explore the mechanisms underlying this transition, the researchers adapted a microwave impedance microscope to withstand cryogenic temperatures and extreme magnetic fields. Using this microscope, they discovered that under a powerful 9 tesla magnetic field, filamentary metallic domains emerge in the manganite films, forming an interconnected network aligned along the axes of the film substrate.
The first ever evidence of a microscopic mechanism for CMR, the discovery of this network greatly enhances our understanding of microscopic phase transitions in thin film manganites. It also marks a major advance in the race toward new memory and switching devices, whose impact promises to revolutionize computing technology.
For more information, please contact:
Dr. Masashi Kawasaki
Dr. Masao Nakamura
Functional Superstructure Team, Emergent Materials Department
RIKEN Advanced Science Institute
Tel: +81-(0)48-467-1111 (ex. 6323) / Fax: +81-(0)48-467-4703
Ms. Tomoko Ikawa (PI officer)
Global Relations Office
Tel: +81-(0)48-462-1225 / Fax: +81-(0)48-462-4715
gro-pr | Research asia research news
The most recent press releases about innovation >>>
Die letzten 5 Focus-News des innovations-reports im Überblick:
Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.
As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...
Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.
Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...
For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.
While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...
An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.
The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...
A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.
Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...