An amplifier design for efficient amplification of linearly polarized fundamental mode lasers is presented. The concept was verified by amplifying single-frequency input powers from 1 W to 20 W into output power ranges of 35 W up to 65 W. Beam quality measurements with a mode-analyzer cavity showed only minor beam quality degradation due to the amplification process.

ductance of layer. These dependencies showed that hybridization appears when sheet conductance of layer (σ) exceeds some critical value σcr), the magnitude of which changes in wide range and depends on material and plate orientation. For example, for aforementioned hybrid pair A0 SH0 in potassium niobate σcr = 10−3S. If σ < σcr modes are not coupled, i.e. their dispersion curves do not repulse....

SUMMARY Time-warping is a signal processing technique that, when applied to an isolated measurement of transient that propagates in waveguide, allows contributions from individual mode numbers be and extracted. Dispersion curves for can, turn, recovered. Isolation associated with possible because after time-warping—a special environmentally dependent non-uniform sampling—is applied, the energy ...

The finite-difference (FD) method described here is specially developed to model high-frequency Rayleigh-wave propagation in near-surface mediums. Although many FD programs existed for earthquake research and oil exploration, none has been developed to model high-frequency Rayleigh-wave propagation in near-surface elastic mediums when the source and all receivers are on the free-surface. The sc...

Long-period surface waves are used to map lateral heterogeneities of velocity and anisotropy in the upper mantle. The dispersion curves are expanded in spherical harmonics up to degree 6 and inverted to find the depth structure. The data are corrected for the effect of surface layers and both Love and Rayleigh waves are used. Shear wave velocity and shear polarization anisotropy can be resolved...

The properties of Rayleigh-type surface wave in a linear, homogeneous and transversely isotropic nonlocal micropolar piezoelectric solid half-space are explored. Dispersion relations for derived both charge free electrically shorted cases. Using an algorithm iteration method MATLAB software, the speed Rayleigh is computed relevant material constants. effects nonlocality, angular frequency, micr...

We present data from recent high-energy-density laboratory experiments designed to explore the Rayleigh– Taylor instability under conditions relevant to supernovae. The Omega laser is used to create a blast wave structure that is similar to that of the explosion phase of a core-collapse supernova. An unstable interface is shocked and then decelerated by the planar blast wave, producing Rayleigh...

Near-surface structure investigation plays an important role in studying shallow active faults and has various engineering applications. Therefore, we developed a near-surface method using ambient noise water environment. This newly seismic acquisition technology, fiber-optic distributed acoustic sensing (DAS), was used to acquire from the Yangtze River. The recorded data were processed reconst...

We perform ambient noise tomography of China using the data from the China National Seismic Network and surrounding global and regional stations. For most of the station pairs, we retrieve good Rayleigh waveforms from ambient noise correlations using 18-months of continuous data at all distance ranges across the entire region (over 5000 km) and for periods from 70 s down to about 8 s. We obtain...

SUMMARY Global variations in the propagation of fundamental-mode and overtone surface waves provide unique constraints on low-frequency source properties structure Earth’s upper mantle, transition zone mid mantle. We construct a reference data set multimode dispersion measurements by reconciling large diverse catalogues Love-wave (49.65 million) Rayleigh-wave (177.66 from eight groups worldwide...