| 摘要 |
<p>PURPOSE:To increase an ON/OFF ratio of an optical bistable device and to increase a degree of freedom of design of an optical bistable element by setting the energy of operating light within a range where an absorption coefft. of an (i) layer of a pin diode exhibits decreasing characteristic in accompany with an increase of a reverse bias voltage impressed to the pin diode. CONSTITUTION:In the title optical bistable device, a pin diode 1 for photo generation and photo modulation is connected in series with a negative resistance element 2 and a constant-voltage power source 3. The energy of operating light is set at a higher energy side than that of an absorption peak of an excitor of an (i) layer of the pin diode 1 at a zero bias voltage. In this case, the absorption coefft. of the (i) layer decreases as a reverse bias voltage impressed to the pin diode increases. Accordingly, decrease of transmittance occurs in a light energy region due to its large absorption coefft., but the change of the absorption coefft. by the effect of impressed voltage becomes rather larger. Thus, an optical bistable element having a large ON/OFF ratio and a large degree of freedom of design of the element and obtd. by an easy prepn. method, is obtd.</p> |
