| Автор | J F Scott |
| Автор | Shou-Jong Sheih |
| Дата выпуска | 1990-10-22 |
| dc.description | Near T<sub>c</sub>=846 K barium sodium niobate exhibits a strong thermal focusing of laser light polarized along its optic c axis (focal length F=+2 to +3 cm for 1 W in a 0.45 mm beam waist). The beam convergence theta (T) is proportional to K<sup>-1</sup>(T)dn<sub>c</sub>(T)/dT, where K is the thermal conductivity and n<sub>c</sub> is the c-axis index of refraction. For zero applied field, theta (T) far from T<sub>c</sub> is dominated by the isotropic dn/dT term, which varies as t<sup>2 beta -1</sup>, where t is the reduced temperature and beta is the coexistence curve exponent (approximately <sup>1</sup>/<sub>4</sub> in this tricritical system). However, within a degree or two of T<sub>c</sub>, theta (T) is dominated by K(T), which becomes highly anisotropic and has a cusp-like dip for thermal diffusion along the polar c axis. In the present experiment the authors apply a DC electric field along c and show that a few kV cm<sup>-1</sup> is sufficient to suppress the cusp. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Название | Fluctuation quenching of thermal focusing in Ba<sub>2</sub>NaNb<sub>5</sub>O<sub>15</sub> |
| Тип | lett |
| DOI | 10.1088/0953-8984/2/42/032 |
| Electronic ISSN | 1361-648X |
| Print ISSN | 0953-8984 |
| Журнал | Journal of Physics: Condensed Matter |
| Том | 2 |
| Первая страница | 8553 |
| Последняя страница | 8556 |
| Аффилиация | J F Scott; Dept. of Phys., Colorado Univ., Boulder, CO, USA |
| Аффилиация | Shou-Jong Sheih; Dept. of Phys., Colorado Univ., Boulder, CO, USA |
| Выпуск | 42 |
