| 摘要 |
<p>Provided is a variable optical attenuator for which surface area can easily be increased, for which there is no need to apply an external field except when varying the transmittance, and which can operate at room temperature. In an embodiment of the present invention, there is provided a variable optical attenuator (100) provided with an La1-xSrxMnO3 film (LSMO film (2), where 0.1 < x < 0.7) formed on a substrate (1) in the (210) plane direction, and a magnetization control means (50) for controlling the magnetization (4) of the LSMO film (2) in the film plane. In the variable optical attenuator (100), the light transmittance of the LSMO film (2) is controlled by the control of the magnetization of the LSMO film (2) in the film plane by the magnetization control means (50).</p> |
