They're not exactly the peanut butter and jelly of semiconductors, but when you put them together, something magical happens.
Alone, neither lanthanum aluminate nor strontium titanate exhibit any particularly notable properties. But when they are layered together, they become not only conductive, but also magnetic.
In the current online edition of Nature Physics, researchers at The Ohio State University report the first-ever theoretical explanation to be offered for this phenomenon since it was discovered in 2004.
Understanding how these two semiconductors interact at their interface could someday lead to a different kind of material—one that provides a single platform for computation and data storage, said Mohit Randeria, co-author of the paper and professor of physics at Ohio State.
"The whole question is, how can you take two materials which do not conduct electricity and do not have magnetic properties, make a sandwich out of them and—lo and behold—at the interface tween them, charge begins to flow and interesting magnetic effects happen?" he said.
"It's like taking two pieces of bread and putting them together and having the sandwich filling magically appear."
By making calculations and modeling the basic physical properties of both materials, Randeria's team has hit upon an explanation for the behavior that seems ironic: the interface between two non-magnetic materials exhibits magnetism.
The team showed how the elemental units of magnetism, called "local moments," are formed at the interface of the two materials. They then showed how these moments interact with the conducting electrons to give rise to a magnetic state in which the moments are arranged in an unusual spiral pattern.
If the physicists' explanation is correct, then perhaps someday, electronic devices could be constructed that exploit the interface between two oxides. Theoretically, such devices would combine the computational abilities of a silicon chip with the magnetic data storage abilities of permanent magnets like iron.
"If you had conduction and magnetism available in the same platform, it could be possible to integrate computer memory with data processing. Maybe different kinds of computation would be possible," Randeria said.
But those applications are a long way off. Right now, the physicists hope that their theoretical explanation for the strange magnetic behavior will enable other researchers to perform experiments and confirm it.
Randeria's coauthors included Ohio State postdoctoral researcher Sumilan Banerjee and former doctoral student Onur Erten, who graduated this summer and is about to begin a postdoctoral fellowship at Rutgers, The State University of New Jersey.
This research was sponsored by the U.S. Department of Energy, the National Science Foundation (NSF), and Ohio State's Center for Emergent Materials, one of a network of Materials Research Science and Engineering Centers funded by NSF.
Pam Frost Gorder | EurekAlert!
First evidence on the source of extragalactic particles
13.07.2018 | Technische Universität München
Simpler interferometer can fine tune even the quickest pulses of light
12.07.2018 | University of Rochester
For the first time ever, scientists have determined the cosmic origin of highest-energy neutrinos. A research group led by IceCube scientist Elisa Resconi, spokesperson of the Collaborative Research Center SFB1258 at the Technical University of Munich (TUM), provides an important piece of evidence that the particles detected by the IceCube neutrino telescope at the South Pole originate from a galaxy four billion light-years away from Earth.
To rule out other origins with certainty, the team led by neutrino physicist Elisa Resconi from the Technical University of Munich and multi-wavelength...
For the first time a team of researchers have discovered two different phases of magnetic skyrmions in a single material. Physicists of the Technical Universities of Munich and Dresden and the University of Cologne can now better study and understand the properties of these magnetic structures, which are important for both basic research and applications.
Whirlpools are an everyday experience in a bath tub: When the water is drained a circular vortex is formed. Typically, such whirls are rather stable. Similar...
Physicists working with Roland Wester at the University of Innsbruck have investigated if and how chemical reactions can be influenced by targeted vibrational excitation of the reactants. They were able to demonstrate that excitation with a laser beam does not affect the efficiency of a chemical exchange reaction and that the excited molecular group acts only as a spectator in the reaction.
A frequently used reaction in organic chemistry is nucleophilic substitution. It plays, for example, an important role in in the synthesis of new chemical...
Optical spectroscopy allows investigating the energy structure and dynamic properties of complex quantum systems. Researchers from the University of Würzburg present two new approaches of coherent two-dimensional spectroscopy.
"Put an excitation into the system and observe how it evolves." According to physicist Professor Tobias Brixner, this is the credo of optical spectroscopy....
Ultra-short, high-intensity X-ray flashes open the door to the foundations of chemical reactions. Free-electron lasers generate these kinds of pulses, but there is a catch: the pulses vary in duration and energy. An international research team has now presented a solution: Using a ring of 16 detectors and a circularly polarized laser beam, they can determine both factors with attosecond accuracy.
Free-electron lasers (FELs) generate extremely short and intense X-ray flashes. Researchers can use these flashes to resolve structures with diameters on the...
13.07.2018 | Event News
12.07.2018 | Event News
03.07.2018 | Event News
13.07.2018 | Event News
13.07.2018 | Materials Sciences
13.07.2018 | Life Sciences