Unusual Resistance Hysteresis In N-Layer Graphene Field Effect Transistors Fabricated On Ferroelectric Pb(Zr0.2Ti0.8)O3,
2010
University of Nebraska–Lincoln
Unusual Resistance Hysteresis In N-Layer Graphene Field Effect Transistors Fabricated On Ferroelectric Pb(Zr0.2Ti0.8)O3, X. Hong, J. Hoffman, A. Posadas, K. Zou, C. H. Ahn, J. Zhu
Xia Hong Publications
We have fabricated n-layer graphene field effect transistors on epitaxial ferroelectric Pb(Zr0.2Ti0.8)O3 (PZT) thin films. At low gate voltages, PZT behaves as a high-k dielectric with k up to 100. An unusual resistance hysteresis occurs in gate sweeps at high voltages, with its direction opposite to that expected from the polarization switching of PZT. The relaxation of the metastable state is thermally activated, with an activation barrier of 50–110 meV and a time constant of 6 h at 300 K. We attribute its origin to the slow dissociation/recombination dynamics of water molecules adsorbed at …
Robust Isothermal Electric Control Of Exchange Bias At Room Temperature,
2010
University of Nebraska-Lincoln
Robust Isothermal Electric Control Of Exchange Bias At Room Temperature, Xi He, Ning Wu, Anthony N. Caruso, Elio Vescovo, Kirill D. Belashchenko, Peter A. Dowben, Christian Binek
Kirill Belashchenko Publications
Voltage-controlled spin electronics is crucial for continued progress in information technology. It aims at reduced power consumption, increased integration density and enhanced functionality where non-volatile memory is combined with highspeed logical processing. Promising spintronic device concepts use the electric control of interface and surface magnetization. From the combination of magnetometry, spin-polarized photoemission spectroscopy, symmetry arguments and first-principles calculations, we show that the (0001) surface of magnetoelectric Cr2O3 has a roughness-insensitive, electrically switchable magnetization. Using a ferromagnetic Pd/Co multilayer deposited on the (0001) surface of a Cr2O3 single crystal, we achieve reversible, room-temperature isothermal switching …
