Rare-earth complexes are vital for separation chemistry and useful in many advanced applications including emission and energy upconversion. Here, 2D rare-earth clusters having net charges are formed on a metal surface, enabling investigations of their structural and electronic properties on a one-cluster-at-a-time basis using scanning tunneling microscopy. While these ionic complexes are highly mobile on the surface at ≈100 K, their mobility is greatly reduced at 5 K and reveals stable and self-limiting clusters.
View Article and Find Full Text PDFSuperconductivity in graphene-based systems has recently attracted much attention, as either intrinsic behavior or induced by proximity to a superconductor may lead to interesting topological phases and symmetries of the pairing function. A prominent system considers the pairing to have chiral symmetry. The question arises as to the effect of possible spin-orbit coupling on the resulting superconducting quasiparticle (QP) spectrum.
View Article and Find Full Text PDFBackground: Despite surgical reconstruction and extensive rehabilitation, persistent quadriceps inhibition, gait asymmetry, and functional impairment remain prevalent in patients after anterior cruciate ligament (ACL) injury. A combination of reports have suggested underlying central nervous system adaptations in those after injury govern long-term neuromuscular impairments. The classic assumption has been to attribute neurophysiologic deficits to components of injury, but other factors across the continuum of care (e.
View Article and Find Full Text PDFObjectives: Determine the effect of visual-based motor and cognitive dual tasking on postural stability in those with anterior cruciate ligament reconstruction relative to matched controls.
Design: Cohort study.
Methods: Fourteen volunteers with history of anterior crucaite ligament reconstruction were matched with fourteen healthy controls.
J Phys Condens Matter
July 2018
We undertake a theoretical study of the role of spin orbit interactions in a silicon double quantum dot. We propose that an accurate estimate of the strength of this interaction can be obtained through the study of the return probability of the double occupation singlet state in a magnetic field, as the system is gated dynamically across the relevant states in the low energy two-electron manifold. Landau-Zener type of processes involving appropriate control of voltage pulses across neighboring avoided crossings in the energy spectrum of the system are utilized to explore the system dynamics.
View Article and Find Full Text PDFKondo resonances in heterostructures formed by magnetic molecules on a metal require free host electrons to interact with the molecular spin and create delicate many-body states. Unlike graphene, semiconducting graphene nanoribbons do not have free electrons due to their large bandgaps, and thus they should electronically decouple molecules from the metal substrate. Here, we observe unusually well-defined Kondo resonances in magnetic molecules separated from a gold surface by graphene nanoribbons in vertically stacked heterostructures.
View Article and Find Full Text PDFThe transport properties of nanostructured systems are deeply affected by the geometry of the effective connections to metallic leads. In this work we derive a conductance expression for a class of interacting systems whose connectivity geometries do not meet the Meir-Wingreen proportional coupling condition. As an interesting application, we consider a quantum dot connected coherently to tunable electronic cavity modes.
View Article and Find Full Text PDFOsteoarthritis is the most common cause of arthritis and one of the main causes of chronic pain. Although opioids are frequently employed for chronic pain treatment, their usage for osteoarthritis pain remains controversial due to the associated adverse effects. Most guidelines reserve their use for refractory pain in patients with hip and knee osteoarthritis.
View Article and Find Full Text PDFBackground: Shoulder instability can cause both soft tissue injury and bone defects, requiring both computed tomography (CT) and magnetic resonance imaging (MRI) for a thorough workup, which results in high patient costs and radiation exposure. Prior studies in cadaveric and nonclinical models have shown promise in assessing preoperative bone loss utilizing MRI.
Purpose: To evaluate the utility of MRI in detecting and evaluating glenoid bone defects in a clinical setting.
Broken symmetries in graphene affect the massless nature of its charge carriers. We present an analysis of scattering by defects in graphene in the presence of spin-orbit interactions (SOIs). A characteristic constant ratio (≃2) of the transport to elastic times for massless electrons signals the anisotropy of the scattering.
View Article and Find Full Text PDFWe study a one-orbital Anderson impurity in a two-dimensional electron bath with Rashba spin-orbit interactions in the Kondo regime. The spin SU(2) symmetry-breaking term couples the impurity to a two-band electron gas. A Schrieffer-Wolff transformation shows the existence of the Dzyaloshinsky-Moriya interaction away from the particle-hole symmetric impurity state.
View Article and Find Full Text PDFMagnetoelectric effects at the atomic scale are demonstrated to afford unique functionality. This is shown explicitly for a quantum corral defined by a wall of magnetic atoms on a metal surface where spin-orbit coupling is observable. We show these magnetoelectric effects allow one to control the properties of systems placed inside the corral as well as their electronic signatures; they provide powerful alternative tools for probing electronic properties at the atomic scale.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
November 2009
We study two quantum dots embedded in the arms of an Aharonov-Bohm ring threaded by a magnetic flux. This system can be described by an effective one-impurity Anderson model with an energy- and flux-dependent density of states. For specific values of the flux, this density of states vanishes at the Fermi energy, yielding a controlled realization of the pseudogap Kondo effect.
View Article and Find Full Text PDFWe develop a realistic model of Rabi oscillations in a quantum-dot photodiode. Based in a multiexciton density matrix formulation we show that for short pulses the two-level model fails and higher levels should be taken into account. This affects some of the experimental conclusions, such as the inferred efficiency of the state rotation (population inversion) and the deduced value of the dipole interaction.
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