672 citations · 3.1k across the 69 of their papers we have counts for
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Symmetry, Disorder and Transport Through Altermagnetic Quantum Dots and Their Antiferromagnetic Twins
George Kirczenow
Altermagnetic crystals resemble antiferromagnets in that they have no macroscopic magnetization, but unlike antiferromagnets they exhibit spin-split band structures. Here the trans…
How to Make a Pristine Tellurium Atomic Helix
George Kirczenow
Tellurium atomic helices are currently attracting increasing attention. However, to date individual tellurium atomic helices have only been grown encapsulated in host materials. A…
On the Nature of Tellurium Atomic Helices
George Kirczenow
A theoreticsal study of single, double and triple hydrogen-terminated chains of tellurium atoms is presented. Surprisingly, H-terminated single chains with 3 Te atoms per unit cell…
Strong Spin Filtering by Silicon Nanoparticles with Adsorbed Bismuth Atom Clusters: Role of Symmetry and Electrostatic Control of the Direction of the Spin Polarization
Alireza Saffarzadeh, George Kirczenow
We present a theoretical study, based on density functional theory and tight binding modeling, of the electronic structure and spin transport properties of silicon nanoparticles wi…
Nearly perfect spin-filtering in curved two-dimensional topological insulators
Alireza Saffarzadeh, George Kirczenow
The spintronic properties of curved nanostructures derived from two-dimensional topological insulators (2DTI's) are explored theoretically with density functional theory-based (DFT…
Mechanisms of jump to contact and conductance plateau formation in copper atomic junctions in vacuum and aqueous environments
Alireza Saffarzadeh, George Kirczenow
The interplay between groups of water molecules and single-atom contacts, as reflected in the electrical conductances and mechanical forces of copper atomic junctions, is explored…
Valley filters, accumulators, and switches induced in graphene quantum dots by lines of adsorbed hydrogen atoms
Mohammadhadi Azari, George Kirczenow
We present electronic structure and quantum transport calculations that predict conducting channels induced in graphene quantum dots by lines of adsorbed hydrogen atoms to function…
Thermoelectric voltage switching in gold atomic wire junctions
Alireza Saffarzadeh, Firuz Demir, George Kirczenow
We explore the thermoelectric properties of gold atomic chains bridging gold electrodes by means of \textit{ab initio} and semi-empirical calculations, and heuristic reasoning. We…
Gate-tunable valley currents, non-local resistances and valley accumulation in bilayer graphene nanostructures
Mohammadhadi Azari, George Kirczenow
Using the Büttiker-Landauer formulation of transport theory in the linear response regime, the valley currents and non-local resistances of bilayer graphene nanostructures with bro…
Malleability at the extreme nanoscale: Slow and fast quakes of few-body systems
Alireza Saffarzadeh, George Kirczenow
We explore the malleability of ultra-small metal nanoparticles by means of ab initio calculations. It is revealed that, when strained, such nanoparticles exhibit complex behavior,…
Rashba-Dirac cones at the tungsten surface: Insights from a tight-binding model and thin film subband structure
George Kirczenow
A tight-binding model of bcc tungsten that includes spin-orbit coupling is developed and applied to the surface states of (110) tungsten thin films. The model describes accurately…
Valley currents and non-local resistances of graphene nanostructures with broken inversion symmetry from the perspective of scattering theory
George Kirczenow
Valley currents and non-local resistances of graphene nanostructures with broken inversion symmetry are considered theoretically in the linear response regime. Scattering state wav…
Coulomb bound states and resonances due to groups of Ca dimers adsorbed on suspended graphene
Alireza Saffarzadeh, George Kirczenow
The electronic bound states and resonances in the vicinity of the Dirac point energy due to the adsorption of calcium dimers on a suspended graphene monolayer are explored theoreti…
Mechanism of the enhanced conductance of a molecular junction under tensile stress
Alireza Saffarzadeh, Firuz Demir, George Kirczenow
Despite its fundamental importance for nano physics and chemistry and potential device applications, the relationship between atomic structure and electronic transport in molecular…
Voltage-controlled spin injection with an endohedral fullerene CoC dimer
Alireza Saffarzadeh, George Kirczenow
Spin-dependent transport through an endohedral fullerene Co@C dimer with gold electrodes is explored theoretically using density functional and extended Hückel theory. Densi…
Switching of a Quantum Dot Spin Valve by Single Molecule Magnets
Fatemeh Rostamzadeh Renani, George Kirczenow
We explore theoretically the spin transport in nanostructures consisting of a gold quantum dot bridging nonmagnetic electrodes and two Mn12-Ph single molecule magnets (SMMs) that a…
Lateral spin injection and detection through electrodeposited Fe/GaAs contacts
Sarmita Majumder, Bartek Kardasz, George Kirczenow +2
Efforts to achieve efficient injection of spin-polarized electrons into a semiconductor, a key prerequisite for developing electronics that exploit the electron's spin degree of fr…
Scanning tunneling spectroscopy and Dirac point resonances due to a single Co adatom on gated graphene
Alireza Saffarzadeh, George Kirczenow
Based on the standard tight-binding model of the graphene -band electronic structure, the extended Hückel model for the adsorbate and graphene carbon atoms, and spin splittings…
Tight Binding Model of Mn12 Single Molecule Magnets: Electronic and Magnetic Structure and Transport Properties
Fatemeh Rostamzadeh Renani, George Kirczenow
We describe and analyze a tight-binding model of single molecule magnets (SMMs) that captures both the spin and spatial aspects of the SMM electronic structure. The model generaliz…
Self-consistent Hartree theory of the role of electron-electron interactions in the electronic structure and conductance quantization of graphene nanoconstrictions
S. Ihnatsenka, G. Kirczenow
We present self-consistent calculations of electron transport in graphene nanoconstrictions within the Hartree approximation. We consider suspended armchair ribbons with V-shaped c…
Ligand-based transport resonances of single-molecule magnet spin filters: Suppression of the Coulomb blockade and determination of the orientation of the magnetic easy axis
Fatemeh Rostamzadeh Renani, George Kirczenow
We investigate single molecule magnet transistors (SMMTs) with ligands that support transport resonances. We find the lowest unoccupied molecular orbitals of Mn12-benzoate SMMs (wi…
Dirac Point Resonances, Transport Gaps and Conductance Quantization in Graphene Nanoribbons with Adsorbed Atoms and Molecules
S. Ihnatsenka, G. Kirczenow
We present calculations of electronic quantum transport in graphene nanoribbons with adsorbed H, F, OH and O, based on a tight binding model derived from extended Huckel theory. Th…
Modulation of Electrical Conduction Through Individual Molecules on Silicon by the Electrostatic Fields of Nearby Polar Molecules: Theory and Experiment
George Kirczenow, Paul G. Piva, Robert A. Wolkow
We report on the synthesis, scanning tunneling microscopy (STM) and theoretical modeling of the electrostatic and transport properties of one-dimensional organic heterostructures c…
Understanding the electroluminescence emitted by single molecules in scanning tunneling microscopy experiments
John Buker, George Kirczenow
We explore theoretically the electroluminescence of single molecules. We adopt a local-electrode framework that is appropriate for scanning tunneling microscopy (STM) experiments w…