Photon interference among distant quantum emitters is a promising method to generate large scale quantum networks. Interference is best achieved when photons show long coherence times. For the nitrogen-vacancy defect center in diamond we measure the coherence times of photons via optically induced Rabi oscillations. Experiments reveal a close to Fourier-transform (i.e., lifetime) limited width ...

We report scanning tunneling spectroscopy studies of the electronic structure of 1.5–3 nm 001 textured MgO layers grown on 001 Fe. Thick MgO layers exhibit a bulklike band gap, 5–7 eV, and sparse, localized defect states with characteristics attributable to oxygen and, in some cases, Mg vacancies. Thin MgO layers exhibit an electronic structure indicative of interacting defect states forming ba...

Molecular dynamic simulation method has been employed to consider the critical buckling force, pressure, and strain of pristine and defected single-walled carbon nanotube (SWCNT) under axial compression. Effects of length, radius, chirality, Stone-Wales (SW) defect, and single vacancy (SV) defect on buckling behavior of SWCNTs have been studied. Obtained results indicate that axial stability of...

Despite recent progress in nano-optomechanics, active control of optical fields at the nanoscale has not been achieved with an on-chip nano-electromechanical system (NEMS) thus far. Here we present a new type of hybrid system, consisting of an on-chip graphene NEMS suspended a few tens of nanometres above nitrogen-vacancy centres (NVCs), which are stable single-photon emitters embedded in nanod...

We present a systematic study to elucidate the role of triple junctions (TJs) and their constituent grain boundaries on the structural stability of nanocrystalline materials. Using atomistic simulations along with the nudge elastic band calculations, we explored the atomic structural and thermodynamic properties of TJs in three different fcc materials. We found that the magnitude of excess ener...

We computed the atomic shift sizes of closest adjacent atoms adjoining (001) surface F-center at ABO3 perovskites. They are significantly larger than bulk F-center. In perovskite matrixes, electron charge is stronger confined in interior oxygen vacancy vacancy. The formation energy on smaller bulk. This microscopic distinction stimulates segregation from to their surfaces. created defect level ...

Using computer simulation techniques the defect structure and oxygen ion migration mechanism of oxide pyrochlores (eg. Gd2Zr207) was investigated in order to explain the decreased activation enthalpy for oxygen ion conductivity as a function of order. Shell model potentials were found to be necessary in order to obtain sufficiently accurate physical properties for the pyrochlore compound. The o...

The harsh irradiation environment poses serious threat to the structural integrity of leading candidate for plasma-facing materials, tungsten (W), in future nuclear fusion reactors. It is thus essential to understand the radiation-induced segregation of native defects and impurities to defect sinks, such as grain boundaries (GBs), by quantifying the segregation energetics. In this work, molecul...

We have investigated the reconstruction, electronic and magnetic properties of graphene nanoribbons using density functional theory structure optimization and electronic structure calculations. In order to obtain proper edge states and their spin polarizations, we generate wide enough edge hydrogenated graphene nanoribbons that have not only mostly considered armchair and zigzag geometries both...

Abstract In this study, radiation-induced precipitation of transmutation products is addressed via the development a new solute and vacancy concentration dependant Ising model for W–Re–Os system. This includes interactions between both Os Re atoms with vacancies, thus facilitating more representative simulations in fusion reactor components. Local dependencies are introduced W–Re, W–Os Re–Os pa...