Research - IRG2

IRG2 - Polarization-Enabled Electronic Phenomena
IRG2 - Polarization-Enabled Electronic Phenomena

This IRG was evolved from the extremely successful SuperSeed Project "Polarization Coupled Memristive Behavior in Oxide Heterostructures (Nov. 2014).

The IRG is aimed at exploring and exploiting ferroelectric (FE) polarization as a state variable that allows realization of polarization-controlled electronic, transport, and other functional properties of oxide, organic, and hybrid FE-based structures. This involves ferroelectrically induced resistive switching phenomena and the associated memristive behavior, FE modulation of electronic confinement at the hybrid FE/semiconductor and organic interfaces, as well as development of novel functional systems based on newly synthesized organic ferroelectrics where molecular interactions are responsible for macroscopic dipole ordering. These scientifically rich problems comprise the involvement of multiple degrees of freedom, the critical role of interfaces, and the interplay between physical and chemical properties at the nanoscale. They require comprehensive fundamental understanding and hold a lot of promise for technological innovations, including new paradigms for data storage and conceptually novel photovoltaic applications.


IRG 2 Researchers

Alexei Gruverman (coordinator) - PFM, CAFM

Stephen Ducharme - Langmuir-Blodgett, dielectric testing

Axel Enders - STM

Chang-Beom Eom - PLD

Xia Hong - Oxide sputtering, nanofab

Jinsong Huang - Hybrid structures

Alexander Sinitskii - Chem. synthesis, devices

Andrei Sokolov - Laser MBE

Evgeny Tsymbal - Theory spin transport and oxide FE

Xiao Cheng Zeng - Theory organic FE

 

 

IRG2

Research Thrust 1:
Polarization-controlled Electronic Transport

Thrust 1 is focused on the electrically controlled transport properties in tunneling systems where FE polarization drives giant resistive switching effects through the modulation of the tunneling barrier and induced metalinsulator transitions at the interface.

Topics:

  • Switchable interface resistance
  • TER driven by interfacial phase transitions
  • Interface chemistry effect on TER
  • Voltage-free control of TER
IRG2

Research Thrust 2:
Polarization-enabled Functional Hybrid Structures

Thrust 2 is centered on polarization-enabled electronic properties of hybrid FE interfaces where electronic confinement gives rise to novel phenomena, which are promising for unconventional electronic devices with new functionalities.

Topics:

  • Polarization-mediated modulation of graphene electronic properties
  • Polarization-induced phase transitions in shape-memory alloys
  • Polarization-enhanced photovoltaic effects
IRG2

Research Thrust 3:
Polarization States in Low-dimension Molecular Ferroelectrics

Thrust 3 is focused on polarization states in novel low-dimensional molecular ferroelectrics where macroscopic ordering is controlled at the molecular level providing new approaches towards polarization-functionalized heterostructures.

Topics:

  • Charge transfer complexes
  • Planar proton-transfer systems
  • Molecular toggling systems

 

IRG 2 Highlights:


» Nature Communications 2014
H. Lu, A. Lipatov, S. Ryu, D. J. Kim, M. Y .Zhuravlev, C. B. Eom, E. Y. Tsymbal, A. Sinitskii, and A. Gruverman, “Ferroelectric tunnel junctions with graphene electrodes,” Nature Comm. 5, 5518 (2014).

» Nano Letters 2014
R. G. P. McQuaid, A. Gruverman, J. F. Scott, and J. M. Gregg, “Exploring vertex interactions in ferroelectric flux-closure domains,” Nano Lett. 14, 4230-4237 (2014).