Probing crossover from analogous weak antilocalization to localization by an Aharonov-Bohm interferometer on topological insulator surface

We propose a scanning tunneling microscopy Aharonov-Bohm (AB) interferometer on the surface of a topological insulator (TI) to probe the crossover from analogous weak antilocalization (WAL) to weak localization (WL) phenomenon via the AB oscillations in spin-resolved local density of states (LDOS). Based on our analytical and numerical results, we show that with increasing the energy gap of TI surface states, the $\Phi_{0}/2$=$hc/2e$ periodic AB oscillations in spin-resolved LDOS gradually transit into the $\Phi_{0}$ periodic oscillations.Comment: 4.2 APL pages, 2 figure

Aharonov-Bohm oscillations in the local density of topological surface states

We study Aharonov-Bohm (AB) oscillations in the local density of states (LDOS) for topological insulator (TI) and conventional metal Au(111) surfaces with spin-orbit interaction, which can be probed by spin-polarized scanning tunneling microscopy. We show that the spacial AB oscillatory period in the total LDOS is a flux quantum $\Phi_{0}\mathtt{=}hc/e$ (weak localization) in both systems. Remarkably, an analogous weak antilocalization with $\Phi_{0}/2$ periodic spacial AB oscillations in spin components of LDOS for TI surface is observed, while it is absent in Au(111).Comment: 4 APL pages, 3 figure

Quantum Corrals and Quantum Mirages on the Surface of a Topological Insulator

We study quantum corrals on the surface of a topological insulator (TI). Different resonance states induced by nonmagnetic (NM), antiferromagnetic (AFM), and ferromagnetic (FM) corrals are found. Intriguingly, the spin is clearly energy-resolved in a FM corral, which can be effectively used to operate surface carrier spins of TI. We also show that an observable quantum mirage of a magnetic impurity can be projected from the occupied into the empty focus of a FM elliptic corral, while in NM and AFM corrals the mirage signal becomes negligibly weak. In addition, the modulation of the interaction between two magnetic impurities in the quantum corrals is demonstrated. These prominent effects may be measured by spin-polarized STM experiments.Comment: 5 PRB pages, 4 figure

Observation and management of shallow anterior chamber after glaucoma surgery

AIM: To analyze the cause and management of shallow anterior chamber after glaucoma surgery.<p>METHODS: The cause and management of shallow anterior chamber after glaucoma surgery on 298 cases(462 eyes)were analyzed retrospectively.<p>RESULTS: In 298 cases(462 eyes), 99 eyes(21.4%)had shallow anterior chamber. In 358 eyes treated with trabeculectomy, 77 eyes(21.5%)had shallow anterior chamber. In 85 eyes treated with trabeculectomy+MMC(mitomycin C), 20 eyes(23.5%)had shallow anterior chamber. In 19 eyes treated with trabeculectomy combined with cataract phacoemulsification and intraocular lens implantation, 2 eyes(10.53%)had shallow anterior chamber. Shallow anterior chamber appeared at 1 day to 5 days postoperatively. Forty-two eyes(42.4%)were with excessive filtering, 6 eyes(6.1%)with malignant glaucoma, 29 eyes(29.3%)with choroidal detachment, 2 eyes(2.0%)with malignant glaucoma complicated by choroidal detachment. Of 99 eyes with shallow anterior chamber, anterior chamber of 79 eyes recovered treated by nonsurgical methods, 20 eyes treated by operation.<p>CONCLUSION: The common cause of shallow anterior chamber after glaucoma surgery was preoperative high intraocular pressure, inflammation, excessive filtering, conjunctival flap flushing and choroidal detachment. Most cases can be managed with nonsurgical methods. Surgical interference should be taken if necessary

A Descriptive Model of Robot Team and the Dynamic Evolution of Robot Team Cooperation

At present, the research on robot team cooperation is still in qualitative analysis phase and lacks the description model that can quantitatively describe the dynamical evolution of team cooperative relationships with constantly changeable task demand in Multi-robot field. First this paper whole and static describes organization model HWROM of robot team, then uses Markov course and Bayesian theorem for reference, dynamical describes the team cooperative relationships building. Finally from cooperative entity layer, ability layer and relative layer we research team formation and cooperative mechanism, and discuss how to optimize relative action sets during the evolution. The dynamic evolution model of robot team and cooperative relationships between robot teams proposed and described in this paper can not only generalize the robot team as a whole, but also depict the dynamic evolving process quantitatively. Users can also make the prediction of the cooperative relationship and the action of the robot team encountering new demands based on this model. Journal web page & a lot of robotic related papers www.ars-journal.co

Poly[[di-μ3-nicotinato-μ3-oxalato-samarium(III)silver(I)] dihydrate]

In the title three-dimensional heterometallic complex, {[AgSm(C6H4NO2)2(C2O4)]·2H2O}n, the SmIII ion is eight-coordinated by four O atoms from four different nicotinate ligands and four O atoms from two different oxalate ligands. The three-coordinate AgI ion is bonded to two N atoms from two different nicotinate anions and one O atom from an oxalate anion. These metal coordination units are connected by bridging nicotinate and oxalate ligands, generating a three-dimensional network. The uncoordinated water mol­ecules link the carboxyl­ate groups via O—H⋯O hydrogen bonding. The crystal structure is further stabilized by hydrogen bonds between the water mol­ecules