Bulk and boundary g2g_2 factorized S-matrices

We investigate the $g_2$-invariant bulk (1+1D, factorized) $S$-matrix constructed by Ogievetsky, using the bootstrap on the three-point coupling of the vector multiplet to constrain its CDD ambiguity. We then construct the corresponding boundary $S$-matrix, demonstrating it to be consistent with $Y(g_2,a_1\times a_1)$ symmetry.Comment: 7 page

The full set of cnc_n-invariant factorized SS-matrices

We use the method of the tensor product graph to construct rational (Yangian invariant) solutions of the Yang-Baxter equation in fundamental representations of $c_n$ and thence the full set of $c_n$-invariant factorized $S$-matrices. Brief comments are made on their bootstrap structure and on Belavin's scalar Yangian conserved charges.Comment: 10p

3D surface topography and reflectivity of anisotropic etched silicon micromirrors for BioMEMS

This paper examines wet and dry fabrication of vertical micro-mirrors in (110) silicon for use in an innovative BioMEMS integrating gripping and micro force sensing functionalities. Wet anisotropic chemical etching in potassium hydroxide (KOH) and tetramethyl ammonium hydroxide (TMAH) with and without isopropanol alcohol (IPA) additive was examined. Deep Reactive Ion Etched samples were produced using inductive coupled process. 3D surface roughness of samples was examined using scanning electron microscope, interferometric profilometer and atomic force microscopy. An optic fiber displacement sensor was exploited to measure the reflectivity of uncoated or coated samples with evaporated metallic thin film. The research aimed to find optimal fabrication technique for fabricating vertical micro-mirrors in polymer based BioMEMS. TMAH etched silicon samples with surface roughness R a = 15.1 nm showed highest reflectivity of all structures fabricated, reflectivity was more than doubled by adding a 10 nm layer of evaporated aluminum coating

Flame sprayed dielectric coatings improve heat dissipation in electronic packaging

Heat sinks in electronic packaging can be flame sprayed with dielectric coatings of alumina or beryllia and finished off with an organic sealer to provide high heat and electrical resistivity

Affine quantum groups

Affine quantum groups are certain pseudo-quasitriangular Hopf algebras that arise in mathematical physics in the context of integrable quantum field theory, integrable quantum spin chains, and solvable lattice models. They provide the algebraic framework behind the spectral parameter dependent Yang-Baxter equation. One can distinguish three classes of affine quantum groups, each leading to a different dependence of the R-matrices on the spectral parameter: Yangians lead to rational R-matrices, quantum affine algebras lead to trigonometric R-matrices and elliptic quantum groups lead to elliptic R-matrices. We will mostly concentrate on the quantum affine algebras but many results hold similarly for the other classes. After giving mathematical details about quantum affine algebras and Yangians in the first two section, we describe how these algebras arise in different areas of mathematical physics in the three following sections. We end with a description of boundary quantum groups which extend the formalism to the boundary Yang-Baxter (reflection) equation.Comment: Contribution to the Encyclopedia of Mathematical Physic

Conserved Charges and Supersymmetry in Principal Chiral Models

We report on investigations of local (and non-local) charges in bosonic and supersymmetric principal chiral models in 1+1 dimensions. In the bosonic PCM there is a classically conserved local charge for each symmetric invariant tensor of the underlying group. These all commute with the non-local Yangian charges. The algebra of the local charges amongst themselves is rather more subtle. We give a universal formula for infinite sets of mutually commuting local charges with spins equal to the exponents of the underlying classical algebra modulo its Coxeter number. Many of these results extend to the supersymmetric PCM, but with local conserved charges associated with antisymmetric invariants in the Lie algebra. We comment briefly on the quantum conservation of local charges in both the bosonic and super PCMs.Comment: 18 pages, LaTeX. Revised and up-dated version based on conference talks by JME and NJ