Two-level magnetic switching of a bilayer epitaxial Fe film grown on a graded stepped W(100) surface is observed using the magneto-optic Kerr effect. Hysteresis loops produced by the film at a location on the curved W(100) surface corresponding to a vicinal angle of 6.4 degrees exhibit two abrupt jumps in magnetization following spin orientation perpendicular to the steps resulting from surface...

Using a linear optical diffraction method, we have experimentally studied the long predicted diffusion anomalous behavior for H/W(100) near the reconstructive phase transition of the W(100) substrate. This anomaly manifests itself in the form of a strong dip in the diffusion coefficient D at the transition temperature T(C). We interpret the strong reduction of D as a result of the diverging fri...

The clean Ta(100) surface and some aspects of hydrogen adsorption have been studied by LEED and AES. The thorough examination of LEED patterns did not provide any evidence for an atomic reconstruction of the clean surface over the entire temperature range investigated, 150-600 K. The r-factor analysis used for comparison between measured and calculated IV spectra yields a contraction of the top...

A 100 W-class all-fiber linearly-polarized single-mode fiber laser at 1120 nm with an optical efficiency of 50% was demonstrated. The laser consists of a 4.2 m long Yb-doped polarization maintaining fiber with a core diameter of 10 μm and a pair of FBGs written in matched passive fiber. Linearly polarized output with a polarization extinction ratio of 15 dB is achieved by a cavity that selects ...

We experimentally demonstrate an 100 Gbit/s hybrid optical fiber-wireless link by employing photonic heterodyning up-conversion of optical 12.5 Gbaud polarization multiplexed 16-QAM baseband signal with two free running lasers. Bit-error-rate performance below the FEC limit is successfully achieved for air transmission distances up to 120 cm.

The apex atom plays a key role in STM tunneling, in particular if subtle effects like atomic and chemical resolution on metal alloys are considered. In order to provide comprehensive data on the electronic structure of realistic tips we have calculated tungsten (100) films with single apex atoms by first principles molecular dynamics and full potential methods. Molecular dynamics using ultrasof...

We report on a Tm:fiber master oscillator power amplifier (MOPA) system producing 109 W CW output power, with >15 dB polarization extinction ratio, sub-nm spectral linewidth, and M2 <1.25. The system consists of polarization maintaining (PM) fiber and PM-fiber components including tapered fiber bundle pump combiners, a single-mode to large mode area mode field adapter, and a fiber-coupled isola...

Making use of an interferometric diagnostic system, we analyze the thermo-mechanical distortions taking place in the slab shaped ceramic Nd:YAG active medium of a 100 W class laser. These distortions are collected in different pumping regimes, both in static situations and during transient warm-up, and compared to the results of computer simulations. This procedure enables us to determine the r...

A surprising magnetic behavior of 3d transition-metal monolayers on the (100) tungsten surface has been reported recently [Ferriani et al., 2005]. The tendency to ferromagnetic (V, Cr, Mn) vs. antiferromagnetic (Fe, Co) order in these layers differs significantly from the situation on many other substrates, e.g. on W(110), Cu(100) or Pd(100). The aim of our work is to explore further the proper...