13 April 2016

Understanding the physics behind a promising kind of resistor

Schematic representation of the shock-wave evolution Schematic representation of the shock-wave evolution

Scientists theorize, and demonstrate, that a tiny shock wave of oxygen is the key to how nanoscale transistors work.

First, some background

Electronic memories in devices such as flash drives rely on silicon, a semiconductor, to store information. Scientists have been studying how a very different class of materials, called transition metal oxides (TMOs), might be used to store information. Recent experiments have shown that an applied electric field can change how resistive these materials are. Termed resistive switching, this phenomenon could be exploited to create nanoscale transistors, or "memsistors," that store information in the form of a resistance value.

What is the finding?

Physicists created a model of this resistive switching to understand what was happening at the atomic level. They theorized that in TMO's, so-called "oxygen vacancies" — places in the material’s crystal structure where an oxygen atom is missing — can move through the material when an electric field is applied to it. In fact, the scientists determined that the oxygen vacancies move similar to a tsunami, in the form a shockwave, as depicted in the illustration above. When this wave changes from one part of the device to another, the material's resistance suddenly changes, providing the ability to control the resistive switching process. The TMO can remain in this state until it is induced to revert back.

The scientists' model results were confirmed by experiments on a manganese-oxide device.

Why is this important?

These new insights into the microscopic mechanisms behind resistive switching may help researchers engineer better memory devices based on transition metals.

Who did the research?

Shao Tang1, Federico Tesler2, Fernando Gomez Marlasca3, Pablo Levy3, V. Dobrosavljević1, and Marcelo Rozenberg4

1National High Magnetic Field Laboratory and Florida State University; 2Universidad de Buenos Aires; 3GIA-CAC-CNEA; 4Laboratoire de Physique des Solides, CNRS

Details for scientists

Funding

This research was funded by the following grants: S.T. and V.D. (NSF DMR-1005751 and DMR-1410132 ); M.R.(Project 465 LACUNES No. ANR-13-BS04-0006-01); F. T., F. G. M., P. L., and M. R. (UBACyT 2013-2016 and MinCyT PICT2013-0788 Project MeMOSat)


For more information, contact Vladimir Dobrosavljevic.

Details

  • Research Area: Condensed Matter Technique Development
  • Facility / Program: DC Field
  • Year: 2016
Last modified on 22 April 2016