Interface controlled materials for novel high Tc superconductors

Jak Tchakhalian, University of Arkansas, DMR 0747808

In 21st century majority of technologically developed countries enter the race for novel energy sources with quantum efficiencies comparable to best thermodynamics driven conventional sources (gas, oil etc.) The search for novel superconducting materials which require no cryo-cooling or even have a Tsc at the room temperature constitute the grand challenge of modern condensed matter physics and material science.

In this work the PI and has synthesized and investigated at the Argonne National lab a new class of ultra-thin artificial layered structures composed of oxide metal LaNiO3 and wide band-gap insulator LaAlO3. Such material doesn't exist in nature and given the unit cell thickness of the constituent layers it is largely controlled by the atoms located at the interface between the layers.

With the help of synchrotron radiation the PI and collaborators have discovered that as the material is pushed to the ultimate atomic layer limit, strong electron-electron correlations and quantum confinement in reduced dimensions turnes the superlattice into a new quantum state known as Mott insulator not attainable in the bulk layers. This new Mott ground state is the fundamental building block for high temperature superconductivity as we know from well known cupper oxide based high Tsc superconductiors.

This finding is a vivid example of rational material design on nonoscale to obtain tailored properties not possible in the bulk.

Interface controlled materials for novel high Tsc superconductors

Jak Tchakhalian, University of Arkansas, DMR 0747808

This work opens a new route towards novel rationally designed architectures where desired physical properties are available on demand. Because of its significance this publication was selected among best 2011 results by Argonne National Laboratory.

The possibility of new smart materials demonstrated in this research became a foundation of the PI’s new very popular outreach program “Crazy Materials!”.

In connection to this work my Ph.D. student Jian Liu received the Ovshinsky Award from the American Physics Society.THIS WORK IS ALSO SELECTED AS THE BEST PUBLICATION BY DOE 2011.

Girls and boy scouts participating in a badge event during the “Crazy Materials!” show.