The coherent photogalvanic effect leads to the generation of a current under the absorption interference of coherent beams and allows for the inscription of space-charge gratings leading to a second-order susceptibility (chi((2))). The inscribed grating au ...
We investigate the regularity of the free boundary for the Signorini problem in Rn+1. It is known that regular points are (n−1)-dimensional and C∞. However, even for C∞ obstacles φ, the set of non-regular (or degenerate) points could be very large—e.g. wit ...
We confirm, for the primes up to 3000, the conjecture of Bourgain-Gamburd-Sarnak and Baragar on strong approximation for the Markoff surface modulo primes. For primes congruent to 3 modulo 4, we find data suggesting that some natural graphs constructed fro ...
Spin-wave resonances in pelletized powder of bismuth orthoferrite (BiFeO3) were studied in transmission spectroscopy at frequencies of 0.1–0.75 THz and in the temperature range of 300–650 K. A vector network analyzer with frequency extenders was used in co ...