Related papers: Controlled aggregation of magnetic ions in a semic…
The electronic structure and magnetic properties of pure and doped {Fe$_{16}$N$_2$} systems have been studied in the local-density (LDA) and quasiparticle self-consistent {\emph{GW}} approximations. The {\emph{GW}} magnetic moment of pure…
To be practical, semiconductors need to be doped. Sometimes, to nearly degenerate levels, e.g. in applications such as thermoelectric, transparent electronics or power electronics. However, many materials with finite band gaps are not…
Doping Bi$_2$Se$_3$ by magnetic ions represents an interesting problem since it may break the time reversal symmetry needed to maintain the topological insulator character. Mn dopants in Bi$_2$Se$_3$ represent one of the most studied…
N-type doping of GaAs nanowires has proven to be difficult because the amphoteric character of silicon impurities is enhanced by the nanowire growth mechanism and growth conditions. The controllable growth of n-type GaAs nanowires with…
We predict here that a slab made of a doped semiconductor can exhibit anomalous refraction under the application of a static magnetic field. This anomalous refraction takes place in the far-infrared range and it occurs for any angle of…
The substitution of Mn in the III-V diluted magnetic semiconductors leads to a strong electron scattering on impurities. Besides the features induced in the valence band by the hybridization with the Mn d-states, also the conduction band is…
Using muon spin rotation and infrared spectroscopy we study the relation between magnetism and superconductivity in Ba$ _{1-x} $K$ _{x} $Fe$ _{2} $As$ _{2} $ single crystals from the underdoped to the slightly overdoped regime. We find that…
Recent experiments on Mn-doped ZnS nanocrystals have shown unusual magnetization properties. We describe a nearest-neighbor Heisenberg exchange model for calculating the magnetization ratios of these antiferromagnetically doped crystals, in…
The resistivity, magnetoresistance, and magnetic susceptibility are measured in single crystals of FeTe0.65Se0.35 with Cu, Ni, and Co substitutions for Fe. The crystals are grown by Bridgman's method. The resistivity measurements show that…
Semiconducting single-walled carbon nanotubes (SWCNTs) are a promising thermoelectric material with high power factors after chemical p- or n-doping. Understanding the impact of dopant counterions on charge transport and thermoelectric…
We have developed a new magnetoelectric material based on Ga doped {\alpha}-Fe2O3 in rhombohedral phase. The material is a canted ferromagnet at room temperature and showing magneto-electric properties. The experimental results of electric…
Recent experiments on the amorphous magnetic semiconductor Gd_x Si_{1-x}, Phys. Rev. Lett. 77, 4652 (1996), ibid 83, 2266 (1999), ibid 84, 5411 (2000), ibid 85, 848 (2000), have revealed an insulator-metal transition (i-m-t), as a function…
The self-assembly of iron dots on the insulating surface of NaCl(001) is investigated experimentally and theoretically. Under proper growth conditions, nanometer-scale magnetic iron dots with remarkably narrow size distributions can be…
This paper, based on a presentation at the Spintronics 2001 conference, provides a review of our studies on II-VI and III-V Mn-doped Diluted Magnetic Semiconductors. We use simple models appropriate for the low carrier density (insulating)…
Electrical control of magnetism in a two-dimensional (2D) semiconductor is of great interest for emerging nanoscale low-dissipation spintronic devices. Here, we propose a general approach of tuning magnetic coupling and anisotropy of a van…
We show that a spontaneous strain and spontaneous magnetization can arise in the doped topological insulators with a two-component superconducting vector order parameter. The details of the effects crucially depend on the symmetry of the…
The magnetization dynamics in diluted magnetic semiconductor heterostructures based on (Zn,Mn)Se and (Cd,Mn)Te has been studied experimentally by optical methods and simulated numerically. In the samples with nonhomogeneous magnetic ion…
We present a systematic study of various ways (top gates, local doping, substrate bias) to fabricate and tune multi-dot structures in silicon nanowire multigate MOSFETs (metal-oxide-semiconductor field-effect transistors). The carrier…
While isovalent doping of GaAs (e.g. by In) leads to a repulsion between the solute atoms, two Cr, Mn, or Fe atoms in GaAs are found to have lower energy than the well-separated pair, and hence attract each other. The strong bonding…
Topological insulators doped with magnetic impurities has become a promising candidate for Quantum Anomalous Hall Effect (QAHE) in the dilute doping limit. The crucial factor in realizing the QAHE in these systems is the spontaneous…