| 摘要 |
<p>Apparatus according to the invention comprises a magneto-optic isolator (30). The isolator comprises a magneto-optic member (10) that comprises a single crystal substrate (11) and a single crystal garnet layer (12) on the substrate. The garnet layer comprises a first and a second stratum (13, 14). The composition of the former is chosen such that the lattice constant of the first stratum material is substantially equal to that of the substrate at a first temperature (e.g., room temperature), and is substantially larger than that of the substrate at a second temperature (e.g., the garnet growth temperature) that is higher than the first temperature. The composition of the second stratum is chosen such that the lattice constant of the second stratum is less than that of the substrate at the first temperature, and is less than that of the first stratum at the second temperature. Wafers according to the invention typically are less subject to fracture than analogous prior art wafers.</p> |
