First-principles calculations of size-dependent giant electroresistance effect in nanoscale asymmetric ferroelectric tunnel junctions

ABSTRACTWe studied the transport properties of the Fe/MgO/Fe and Fe/Ag/MgO/Ag/Fe magnetic tunnel junctions (MTJs) with 13-layer MgO barrier under bias voltage based on first-principles calculations. Our results showed that two features determine the TMR value decreases with bias of Fe/MgO/Fe MTJ: (1) interfacial states lying at 1.06 eV in spin down channel (2) the energy level of the spin down Δ1 band of the Fe electrode. Our results showed that an inserted Ag mono-layer at Fe/MgO interface can remarkably improve the TMR effect at a high bias voltage.

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Size-dependent strain in fivefold twins of gold

Acta Crystallographica Section B Structural Science Crystal Engineering and Materials ◽

10.1107/s2052520620014791 ◽

2021 ◽

Vol 77 (1) ◽

pp. 93-98

Author(s):

Hao Wu ◽

Rong Yu ◽

Jing Zhu ◽

Wei Chen ◽

Yadong Li ◽

...

Keyword(s):

Electron Microscopy ◽

First Principles ◽

First Principles Calculations ◽

Geometrical Constraint ◽

Size Dependent ◽

Transmission Electron ◽

Dependent Strain ◽

Low Dimensional ◽

Low Dimensional Materials ◽

Aberration Corrected

Multiple twinned structures are common in low-dimensional materials. They are intrinsically strained due to the geometrical constraint imposed by the non-crystallographic fivefold symmetry. In this study, the strain distributions in sub-10 nm fivefold twins of gold have been analyzed by combining aberration-corrected transmission electron microscopy and first-principles calculations. Bending of atomic planes has been measured by both experiments and calculations, and its contribution to the filling of the angular gap was shown to be size-dependent.

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Size-dependent electronic, optical and photocatalytic properties of Ti3C2O2 quantum dots studied by first-principles calculations

Physica E Low-dimensional Systems and Nanostructures ◽

10.1016/j.physe.2020.114328 ◽

2020 ◽

Vol 124 ◽

pp. 114328

Author(s):

Yi-min Ding ◽

Xiaomin Nie ◽

Huilong Dong ◽

Nopporn Rujisamphan ◽

Youyong Li

Keyword(s):

Quantum Dots ◽

First Principles ◽

Photocatalytic Properties ◽

First Principles Calculations ◽

Size Dependent

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FIRST-PRINCIPLES CALCULATION OF MAGNETO-ELECTRONIC STRUCTURE OF MOLECULE-FERROMAGNET HYBRID TUNNEL JUNCTIONS

Modern Physics Letters B ◽

10.1142/s0217984913502059 ◽

2013 ◽

Vol 27 (28) ◽

pp. 1350205 ◽

Cited By ~ 1

Author(s):

MASOUD ANSARINO ◽

BAHRAM ABEDI RAVAN ◽

YADOLLAH AHMADIZADEH

Keyword(s):

First Principles ◽

Energy Gap ◽

Tunnel Junctions ◽

Local Density ◽

First Principles Calculation ◽

Polymer Interfaces ◽

First Principles Calculations ◽

Polymeric Chains ◽

Bonding Length ◽

Metal Polymer

In this paper, using first-principles calculations the electronic and magnetic structure of trans- and cis-polyacetylene based magnetic tunnel junctions is investigated. Energy minimization calculations are performed to obtain the equilibrium bonding length at the metal/polymer interfaces. Magnetic proximity-induced spin polarization across the polymeric chains is calculated and it is shown that irrespective of the parallel or anti-parallel magnetic configuration of the electrodes the carbon atoms attaching the Fe electrodes get oppositely polarized. Local density of states calculations reveal that, as a result of being attached to the ferromagnetic leads, states are induced in the energy gap region of molecule's px and py orbitals which infers their contribution in electronic transmission of the device.

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Electron correlation effects in the magnetoresistance of Fe/MgO/Fe tunnel junctions: First-principles calculations

Physical Review B ◽

10.1103/physrevb.78.012404 ◽

2008 ◽

Vol 78 (1) ◽

Cited By ~ 3

Author(s):

S. H. Mirhosseini ◽

K. K. Saha ◽

A. Ernst ◽

J. Henk

Keyword(s):

Electron Correlation ◽

First Principles ◽

Tunnel Junctions ◽

First Principles Calculations ◽

Correlation Effects ◽

Electron Correlation Effects

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First principles study of magnetoelectric coupling in Co2FeAl/BaTiO3 tunnel junctions

Physical Chemistry Chemical Physics ◽

10.1039/c5cp01508a ◽

2015 ◽

Vol 17 (22) ◽

pp. 14986-14993 ◽

Cited By ~ 10

Author(s):

Li Yu ◽

Guoying Gao ◽

Lin Zhu ◽

Lei Deng ◽

Zhizong Yang ◽

...

Keyword(s):

First Principles ◽

Critical Thickness ◽

Magnetoelectric Effect ◽

Tunnel Junctions ◽

Magnetoelectric Coupling ◽

First Principles Calculations ◽

First Principles Study

Critical thickness for ferroelectricity and the magnetoelectric effect of Co2FeAl/BaTiO3 multiferroic tunnel junctions (MFTJs) are investigated using first-principles calculations.

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