相关论文: Valence state manipulation of single Fe impurities…
We utilize a single atom substitution technique with spectroscopic imaging in a scanning tunneling microscope (STM) to visualize the anisotropic spatial structure of magnetic and non-magnetic transition metal acceptor states in the GaAs…
Combining density-functional theory calculations and microscopic tight-binding models, we investigate theoretically the electronic and magnetic properties of individual substitutional transition-metal impurities (Mn and Fe) positioned in…
An individual Mn acceptor in GaAs is mapped by Cross-sectional Scanning Tunneling Microscopy (X-STM) at room temperature and a strongly anisotropic shape of the acceptor state is observed. An acceptor state manifests itself as a cross-like…
We report a reversible and hysteretic change in the topography measured with a scanning tunneling microscope near a single Fe dopant in a GaAs surface when a small positive bias voltage is applied. First-principles calculations of the…
The discovery of ferromagnetism in Mn doped GaAs [1] has ignited interest in the development of semiconductor technologies based on electron spin and has led to several proof-of-concept spintronic devices [2-4]. A major hurdle for realistic…
p-d hybridization of transition metal impurities in a semiconductor host is the mechanism that couples valence-band electrons and localized spins. We use scanning tunneling microscopy and spectroscopy combined with density functional theory…
We have performed voltage dependent imaging and spatially resolved spectroscopy on the (110) surface of Te doped GaAs single crystals with a low temperature scanning tunneling microscope (STM). A large fraction of the observed defects are…
We report the direct observation of two mid-gap core d-states of differing symmetry for a single Fe atom embedded in GaAs. These states are distinguished by the strength of their hybridization with the surrounding host electronic structure.…
The electronic properties of shallow acceptors in p-doped GaAs{110} are investigated with scanning tunneling microscopy at low temperature. Shallow acceptors are known to exhibit distinct triangular contrasts in STM images for certain bias…
Magnetic adatoms on surfaces are exchange coupled to their environment, inducing fast relaxation of excited spin states and decoherence. These interactions can be suppressed by inserting decoupling layers between the magnetic adsorbate and…
We report the observation of tunneling anisotropic magnetoresistance effect (TAMR) in the epitaxial metal-semiconductor system Fe/GaAs/Au. The observed two-fold anisotropy of the resistance can be switched by reversing the bias voltage,…
We prove that scanning tunneling microscopy (STM) images of sub-surface Mn atoms in GaAs are formed by hybridization of the impurity state with intrinsic surface states. They cannot be interpreted in terms of bulk-impurity wavefunction…
Spin resonance of single spin centers bears great potential for chemical structure analysis, quantum sensing and quantum coherent manipulation. Essential for these experiments is the presence of a two-level spin system whose energy…
Electronic nematic phases have been proposed to occur in various correlated electron systems and were recently claimed to have been detected in scanning tunneling microscopy (STM) conductance maps of the pseudogap states of the cuprate…
The metallic tip of a scanning force microscope operated at 300 mK is used to locally induce a potential in a fully controllable double quantum dot defined via local anodic oxidation in a GaAs/AlGaAs heterostructure. Using scanning gate…
Using Fe/GaAs Schottky tunnel barriers as electrical spin detectors, we show that the magnitude and sign of their spin-detection sensitivities can be widely tuned with the voltage bias applied across the Fe/GaAs interface. Experiments and…
The conductance profiles of magnetic transition metal atoms, such as Fe, Co and Mn, deposited on surfaces and probed by a scanning tunneling microscope (STM), provide detailed information on the magnetic excitations of such nano-magnets. In…
By substituting S into single-layer FeSe/SrTiO3, chemical pressure is applied to tune its paramagnetic state that is modeled as an incoherent superposition of spin-spiral states. The resulting electronic bands resemble an ordered…
Metal atoms on graphene, when ionized, can act as a point charge impurity to probe a charge response of graphene with the Dirac cone band structure. To understand the microscopic physics of the metal-atom-induced charge and spin…
We report scanning tunneling microscopy studies of individual adatoms deposited on an InSb(110) surface. The adatoms can be reproducibly dropped off from the STM tip by voltage pulses, and impact tunneling into the surface by up to ~100x.…