相关论文: Controlling the TiN electrode work function at the…
Single-electron occupation is an essential component to measurement and manipulation of spin in quantum dots, capabilities that are important for quantum information processing. Si/SiGe is of interest for semiconductor spin qubits, but…
Gray Tin is attracting much more interest as a topological quantum material, which has a precisely controlled composition and can be a material for spintronic devices. However, the spin dynamics in gray Tin is largely unknown. In this…
First principles calculations based on density functional theory, with generalised gradient corrections and ultrasoft pseudopotentials, have been used to simulate solid and liquid aluminium in direct coexistence at zero pressure.…
We formulate and implement Cyclic Density Functional Theory (Cyclic DFT) -- a self-consistent first principles simulation method for nanostructures with cyclic symmetries. Using arguments based on Group Representation Theory, we rigorously…
Density functional theory has become the workhorse of quantum physics, chemistry, and materials science. Within these fields, a broad range of applications needs to be covered. These applications range from solids to molecular systems, from…
Based on our earlier works [Phys. Rev. B 75, 195127 (2007) & J. Chem. Phys. 128, 234703 (2008)], we propose a formally exact and numerically convenient approach to simulate time-dependent quantum transport from first-principles. The…
Transition metal (TM) defects in silicon carbide have favorable spin coherence properties and are suitable as quantum memory for quantum communication. To characterize TM defects as quantum spin-photon interfaces, we model defects that have…
We consider resonant vortices around nodal points of the wavefunction in electron transport through a mesoscopic device. With a suitable choice of the device geometry, the dominating role is played by single vortices of a preferred…
Structure-function relationships constitute an important tool to investigate the fundamental principles of molecular electronics. Most commonly, this involves identifying a potentially important molecular structural element, followed by…
Topological quantum phase transitions are characterised by changes in global topological invariants. These invariants classify many body systems beyond the conventional paradigm of local order parameters describing spontaneous symmetry…
Introducing, observing, and manipulating individual impurities coupled to a host material offers the opportunity to create new device concepts based on single spin and charge states. Because of potential applications in spintronics and…
Thermoelectric performance is of interest for numerous applications such as waste heat recovery and solid state energy conversion, and will be seen to be closely connected to topological insulator behavior. In this context we here report…
The fabrication of micro- and nano-scale silicon electronic devices requires precision lithography and controlled processing to ensure that the electronic properties of the device are optimized. Importantly, the Si-SiO2 interface plays a…
We explore electron transport properties in a quantum wire attached to two metallic electrodes. A simple tight-binding model is used to describe the system and the coupling of the wire to the electrodes (source and drain) is treated through…
Superconducting quantum circuits are promising systems for experiments testing fundamental quantum mechanics on a macroscopic scale and for applications in quantum information processing. We report on the fabrication and characterization of…
Atomistic simulations provide insights into structure-property relations on an atomic size and length scale, that are complementary to the macroscopic observables that can be obtained from experiments. Quantitative predictions, however, are…
By treating the electron-ion interaction as perturbation in the first-principles Hamiltonian, we have calculated the density response functions of a fluid alkali metal to find an interesting charge instability due to anomalous electronic…
Time-dependent density-functional theory (TDDFT) is widely used to describe electronic excitations in complex finite systems with large numbers of atoms, such as biomolecules and nanocrystals. The first part of this paper will give a simple…
We present a first-principles study of the electronic, magnetic, and transport properties of the topological insulator Bi$_{2}$Te$_{3}$ doped with Mn atoms in substitutional (Mn$_{\rm Bi}$) and interstitial van der Waals gap positions…
We analyze the electronic structure of atoms in the first, second and third periods using the electronic kinetic energy density and stress tensor density, which are local quantities motivated by quantum field theoretic consideration,…