BsB_s Semileptonic Decays to DsD_s and Ds∗D_s^* in Bethe-Salpeter Method

Using the relativistic Bethe-Salpeter method, the electron energy spectrum and the semileptonic decay widths of $B^0_s\to D^-_s \ell^+{\nu_\ell}$ and $B^0_s\to D_s^{*-}\ell^+{\nu_\ell}$ are calculated. We obtained large branching ratios, $Br(B_s\to D_se\nu_e)=(2.85\pm0.35)$ and $Br (B_s\to D_s^*e\nu_e)=(7.09\pm0.88)$, which can be easily detected in the future experiment.Comment: 3 pages, 3 figures

Compact and High Performance Dual-band Bandpass Filter Using Resonator-embedded Scheme for WLANs

A compact microstrip dual-band bandpass filter (DBBPF) with high selectivity and good suppression for wireless local area networks (WLANs) is proposed utilizing a novel embedded scheme resonator. Two passbands are produced by a pair of embedded half-wavelength meandered stepped-impedance resonator (MSIR) and a quadwavelength short stub loaded stepped-impedance resonator (SIR) separately. The resonator is fed by folded Tshaped capacitive source-load coupling microstrip feed line, and four transmission zeros are obtained at both sides of the bands to improve selectivity and suppression. Simultaneously, the size of the filter is extermely compact because embedding half-wavelength MSIR only changes the interior configuration of quad-wavelength SIR. To validate the design method, the designed filter is fabricated and measured. Both simulated and measured results indicate that good transmission property has been achieved

Microwave-induced nonequilibrium temperature in a suspended carbon nanotube

Antenna-coupled suspended single carbon nanotubes exposed to 108 GHz microwave radiation are shown to be selectively heated with respect to their metal contacts. This leads to an increase in the conductance as well as to the development of a power-dependent DC voltage. The increased conductance stems from the temperature dependence of tunneling into a one-dimensional electron system. The DC voltage is interpreted as a thermovoltage, due to the increased temperature of the electron liquid compared to the equilibrium temperature in the leads

Statistical Topography of Glassy Interfaces

Statistical topography of two-dimensional interfaces in the presence of quenched disorder is studied utilizing combinatorial optimization algorithms. Finite-size scaling is used to measure geometrical exponents associated with contour loops and fully packed loops. We find that contour-loop exponents depend on the type of disorder (periodic ``vs'' non-periodic) and they satisfy scaling relations characteristic of self-affine rough surfaces. Fully packed loops on the other hand are unaffected by disorder with geometrical exponents that take on their pure values.Comment: 4 pages, REVTEX, 4 figures included. Further information can be obtained from [email protected]