244 citations · 669 across the 17 of their papers we have counts for
17 papers
Density functional theory study of experimentally observed Au/Ge interfaces
Olga Sikora, Małgorzata Sternik, Benedykt R. Jany +3
In recent years, nanostructures with hexagonal polytypes of gold have been synthesised, opening new possibilities in nanoscience and technology. As bulk gold crystallizes in the \t…
Lattice dynamics of endotaxial silicide nanowires
J. Kalt, M. Sternik, B. Krause +17
Self-organized silicide nanowires are considered as main building blocks of future nanoelectronics and have been intensively investigated. In nanostructures, the lattice vibrationa…
Origin of monoclinic distortion and its impact on the electronic properties in KO
Olga Sikora, Dorota Gotfryd, Andrzej Ptok +4
We use the density functional theory and lattice dynamics calculations to investigate the properties of potassium superoxide KO in which spin, orbital, and lattice degrees of f…
Lattice dynamics and polarization-dependent phonon damping in -phase FeSi nanoislands
J. Kalt, M. Sternik, B. Krause +16
We determined the lattice dynamics of metastable, surface-stabilized -phase FeSi nanoislands epitaxially grown on the Si(111) surface with average heights and widths ranging…
Ab initio and nuclear inelastic scattering studies of FeSi/GaAs heterostructures
O. Sikora, J. Kalt, M. Sternik +11
The structure and dynamical properties of the FeSi/GaAs(001) interface are investigated by density functional theory and nuclear inelastic scattering measurements. The stabilit…
Classical and quantum theories of proton disorder in hexagonal water ice
Owen Benton, Olga Sikora, Nic Shannon
It has been known since the pioneering work of Bernal, Fowler and Pauling that common, hexagonal (Ih) water ice is the archetype of a frustrated material : a proton-bonded network…
Spin excitations used to probe the nature of the exchange coupling in the magnetically ordered ground state of PrCaMnO
R. A. Ewings, T. G. Perring, O. Sikora +3
We have used time-of-flight inelastic neutron scattering to measure the spin wave spectrum of the canonical half-doped manganite PrCaMnO, in its magnetic and…
Of chain-based order and quantum spin liquids in dipolar spin ice
Paul McClarty, Olga Sikora, Roderich Moessner +3
Recent experiments on the spin-ice material Dy2Ti2O7 suggest that the Pauling "ice entropy", characteristic of its classical Coulombic spin-liquid state, may be lost at low tempera…
Variational Monte Carlo simulations using tensor-product projected states
Olga Sikora, Hsueh-Wen Chang, Chung-Pin Chou +2
We propose an efficient numerical method, which combines the advantages of recently developed tensor-network based methods and standard trial wave functions, to study the ground st…
Ground state in a half-doped manganite distinguished by neutron spectroscopy
G. E. Johnstone, T. G. Perring, O. Sikora +2
We have measured the spin-wave spectrum of the half-doped bilayer manganite Pr(Ca,Sr)2Mn2O7 in its spin, charge, and orbital ordered phase. The measurements, which extend throughou…
Seeing the light : experimental signatures of emergent electromagnetism in a quantum spin ice
Owen Benton, Olga Sikora, Nic Shannon
The "spin ice" state found in the rare earth pyrochlore magnets Ho2Ti2O7 and Dy2Ti2O7 offers a beautiful realisation of classical magnetostatics, complete with magnetic monopole ex…
Quantum Ice : a quantum Monte Carlo study
Nic Shannon, Olga Sikora, Frank Pollmann +2
Ice states, in which frustrated interactions lead to a macroscopic ground-state degeneracy, occur in water ice, in problems of frustrated charge order on the pyrochlore lattice, an…
Extended quantum U(1)-liquid phase in a three-dimensional quantum dimer model
Olga Sikora, Nic Shannon, Frank Pollmann +2
Recently, quantum dimer models, in which the system can tunnel between different classical dimer configurations, have attracted a great deal of interest as a paradigm for the study…
A quantum liquid with deconfined fractional excitations in three dimensions
O. Sikora, F. Pollmann, N. Shannon +2
Excitations which carry "fractional" quantum numbers are known to exist in one dimension in polyacetylene, and in two dimensions, in the fractional quantum Hall effect. Fractional…
Magnetic excitations in vanadium spinels
N. B. Perkins, O. Sikora
We study magnetic excitations in vanadium spinel oxides AVO (A=Zn, Mg, Cd) using two models: first one is a superexchange model for vanadium S=1 spins, second one includes…
Origin of the Orbital Ordering in LaMnO
Olga Sikora, Andrzej M. Oles
We use the temperature of the structural phase transition to determine the Jahn-Teller (JT) coupling constant in the model derived for LaMnO which includes both the superexchan…
Jahn-Teller Effect and Superexchange in Half-Doped Manganites
Olga Sikora, Andrzej M. Oles
We investigate the stability of the charge exchange (CE) phase within a microscopic model which describes a single plane as in LaSrMnO. The model includes Coulo…