Generalization of Friedberg-Lee Symmetry

We study the possible origin of Friedberg-Lee symmetry. First, we propose the generalized Friedberg-Lee symmetry in the potential by including the scalar fields in the field transformations, which can be broken down to the FL symmetry spontaneously. We show that the generalized Friedberg-Lee symmetry allows a typical form of Yukawa couplings, and the realistic neutrino masses and mixings can be generated via see-saw mechanism. If the right-handed neutrinos transform non-trivially under the generalized Friedberg-Lee symmetry, we can have the testable TeV scale see-saw mechanism. Second, we present two models with the $SO(3)\times U(1)$ global flavour symmetry in the lepton sector. After the flavour symmetry breaking, we can obtain the charged lepton masses, and explain the neutrino masses and mixings via see-saw mechanism. Interestingly, the complete neutrino mass matrices are similar to those of the above models with generalized Friedberg-Lee symmetry. So the Friedberg-Lee symmetry is the residual symmetry in the neutrino mass matrix after the $SO(3)\times U(1)$ flavour symmetry breaking.Comment: 16 pages, no figure, version published in PR

Helical edge and surface states in HgTe quantum wells and bulk insulators

The quantum spin Hall (QSH) effect is the property of a new state of matter which preserves time-reversal, has an energy gap in the bulk, but has topologically robust gapless states at the edge. Recently, it has been shown that HgTe quantum wells realize this novel effect. In this work, we start from realistic tight-binding models and demonstrate the existence of the helical edge states in HgTe quantum wells and calculate their physical properties. We also show that 3d HgTe is a topological insulator under uniaxial strain, and show that the surface states are described by single-component massless relativistic Dirac fermions in 2+1 dimensions. Experimental predictions are made based on the quantitative results obtained from realistic calculations.Comment: 5 page

Animal Agriculture in South Carolina

Livestock Production/Industries,

The cosmological origin of Higgs particles

A proposal of the cosmological origin of Higgs particles is given. We show, that the Higgs field could be created from the vacuum quantum conformal fluctuation of Anti-de Sitter space-time, the spontaneous breaking of vacuum symmetry, and the mass of Higgs particle are related to the cosmological constant of our universe,especially the theoretical estimated mass m$_{H}$ of Higgs particles is m$_{H}=\sqrt{-2\mu ^{2}}$ =$\sqrt{|\Lambda /\pi}$.Comment: 7 pages,no figure

Study of V_LV_L to t tbar at the ILC Including O(alpha_s) QCD Corrections

In the event that the Higgs mass is large or that the electroweak interactions are strongly interacting at high energy, top quark couplings to longitudinal components of the weak gauge bosons could offer important clues to the underlying dynamics. It has been suggested that precision measurements of W_L W_L to t tbar and Z_L Z_L to t tbar might provide hints of new physics. In this paper we present results of O(alpha_s) QCD corrections to V_LV_L to t tbar scattering at the ILC. We find that corrections to cross sections can be as large as 30% and must be accounted for in any precision measurement of VV to t tbar.Comment: 8 pages, 8 figures, Minor changes in wording. uses Revtex

Thermal entanglement of one-dimensional Heisenberg quantum spin chains in magnetic fields

The thermal pairwise entanglement (TE) of the S=1/2 XY chain in a transverse magnetic field is exactly resolved by means of the Jordan-Wigner transformation. It is found that the TE vanishes at a common temperature Tc~0.4843J, which is irrelevant to the field. A thermal quantity is proposed to witness the entangled state. Furthermore, the TE of the S=1/2 antiferromagnetic-ferromagnetic (AF-F) Heisenberg chain is studied by the transfer-matrix renormalization group method.The TEs of the spins coupled by AF and F interactions are found to behave distinctively. The vanishing temperature of the field-induced TE of the spins coupled by F interactions is observed to change with the magnetic field. The results are further confirmed and analyzed by the mean-field theory.Comment: 5 pages, 3 figures, accepted by Phys. Rev.

Modification of the Landau-Lifshitz Equation in the Presence of a Spin-Polarized Current in CMR and GMR Materials

We derive a continuum equation for the magnetization of a conducting ferromagnet in the presence of a spin-polarized current. Current effects enter in the form of a topological term in the Landau-Lifshitz equation . In the stationary situation the problem maps onto the motion of a classical charged particle in the field of a magnetic monopole. The spatial dependence of the magnetization is calculated for a one-dimensional geometry and suggestions for experimental observation are made. We also consider time-dependent solutions and predict a spin-wave instability for large currents.Comment: 4 two-column pages in RevTex, 3 ps-figure

Dynamical Axion Field in Topological Magnetic Insulators

Axions are very light, very weakly interacting particles postulated more than 30 years ago in the context of the Standard Model of particle physics. Their existence could explain the missing dark matter of the universe. However, despite intensive searches, they have yet to be detected. In this work, we show that magnetic fluctuations of topological insulators couple to the electromagnetic fields exactly like the axions, and propose several experiments to detect this dynamical axion field. In particular, we show that the axion coupling enables a nonlinear modulation of the electromagnetic field, leading to attenuated total reflection. We propose a novel optical modulators device based on this principle.Comment: 5 pages, 3 figure

Improvement of a Phosphate Ion-selective Microsensor Using Bis(dibromophenylstannyl)methane as a Carrier

An ionophore-doped sensing membrane phosphate (PO4) microsensor based on bis(dibromophenylstannyl)methane (Bis microsensor) is described. The Bis microsensor showed a Nernstian response. The response of the Bis microsensor was log-linear down to a monohydrogen phosphate ion (HPO42−) concentration of 0.5 μM (corresponding to 1.0 μM of orthophosphate at pH 7.2), whereas the detection limit of PO4-microsensors based on trialkyl/aryltin chloride was 50 μM of HPO42−. The Bis microsensor showed excellent selectivity for HPO42− against nitrite, nitrate, chloride, bicarbonate and sulfate, as compared with PO4 microsensors based on trialkyl/aryltin chloride. Dissolved oxygen, which is known to interfere with the response of a previously developed cobalt-based potentiometric solid-state PO4 microsensor, had no effect on the response of the ionophore-doped sensing membrane-type microsensors described herein. Only OH− (i.e., pH) interfered with the ionophore-doped sensing membrane-type microsensors