| 摘要 |
<p>A magnetoresistance ratio of 200% (absolute value) or more at a given temperature, e.g., at room temperature, in a field of 6T can be achieved in a layer (61) of material of nominal composition XMnOy (X is La and at least one of Ca, Sr and Ba, y in the range 2-3.5), if, after formation of the layer, the layer is heat treated in an oxygen-rich (O2 partial pressure greater than that of air) atmosphere, typically in flowing O2. The temperature and duration of the heat treatment are in the range 300-850 DEG C and 10 minutes - 12 hours, and are selected to result in the desired ratio of 200% or more.</p> |
