Electrochemical driven self-holding optical actuator: from materials to device concepts

在此框架下，我们将开发一种新型的自持电化学驱动的光致动器。我们的主要目标是评估用于致动器的有前途的材料，并表明我们的方法与硅光子学兼容。致动器的目的是控制光子芯片上的光传输。致动原理基于覆盖硅波导的选定区域的混合离子电子导体（MIEC）材料。通过波导传播的光波受到到MIEC材料的近场耦合的影响。作为光调制器的基础材料，我们使用电致变色材料V2 O 5和WO 3。锂和氢都将用作移动的离子用于MIEC材料的嵌入。MIEC材料的离子含量可以通过电化学反应来改变。随着化学计量的这种变化，光学性质，即，折射率和消光系数以及因此在下面的波导中传播的光波的强度和相位将被修改。为了证明使用MIEC材料作为光学致动器的概念，将通过溅射沉积来制造固态多层系统。多层堆叠的电化学性能使得能够通过所施加的电压/电流来调节MIEC材料的离子含量并因此调节其光学性质。将驱动器系统集成到硅光子电路上，研究其光调制能力。为此目的，多层堆叠将沉积在各种硅波导结构的明确限定的区域中，所述硅波导结构之前通过电子束光刻结合反应离子蚀刻制造。从我们的实验中得到的硅波导致动器系统的光学特性进行了比较与模拟，以获得一个致动器材料系统的设计和性能方面的优化性能，从实验和模拟之间的比较，经过几次迭代。

In the framework of this proposal we will develop a novel self-holding electrochemically driven optical actuator. Our key goal is to evaluate promising materials used for the actuator and to show that our approach is compatible with silicon photonics. The purpose of the actuator is the control of light transmission on photonic chips. The actuation principle is based on mixed ionic-electronic conductor (MIEC) materials that cover selected areas of silicon waveguides. Light waves propagating through the wave guide are affected by near-field coupling to the MIEC material. As base material for the optical modulator we use the electrochromic materials V2O5 and WO3. Both lithium and hydrogen will be used as mobile ions for the intercalation of the MIEC material. The ion content of the MIEC material can be changed by electrochemical reactions. With this change in stoichiometry also the optical properties, i.e., the refractive index and the extinction coefficient and thus the intensity and phase of light waves propagating in the underlying waveguide will be modified. In order to prove the concept of using MIEC materials as optical actuators, solid-state multilayer systems will be fabricated by sputter deposition. The electrochemical performance of the multilayer stack enables to adjust the ion content of the MIEC material and thus its optical properties by the voltage/current applied. The optical modulation capability will be studied by integrating the actuator system on silicon photonic circuits. For this purpose, the multilayer stack will be deposited in well-defined areas of various silicon waveguide structures that were fabricated before by means of electron beam lithography in combination with reactive ion etching. The optical properties of the silicon waveguide-actuator system derived from our experiments are compared with simulations in order to obtain an actuator material system with optimized properties in terms of design and performance from the comparison between experiment and simulation after several iterations.