Inverse‐Designed Integrated Nonlinear Optical Switches

Abstract Due to the slowdown of Moore's law, the integrated photonic devices have provided a route to promote the development of large‐scale optical communications with high performance. As one of the essential components of optical routers, an optical switch can fast transmit or block the optical signal. However, most of the integrated optical switches reported to date rely on thermo‐, magneto‐, or electro‐optical effects, which limit applications due to slow response times, large footprint, and complexity fabrication. Here, an integrated nonlinear optical switch designed by the inverse‐design method and fabricated on the SiN platform is introduced. The integrated optical switch is demonstrated with significant intensity‐dependent transmission at 1.5 µm waveband. The polarization‐depended capability is explored by using fundamental polarized lights (transverse electric and transverse magnetic, respectively), which exhibits opposite transmission change trends during the whole power range and opens potential applications such as photonic quantum information processing. In order to address the saturation of Kerr‐nonlinearity in SiN materials at high power, a MoS 2 /SiN hybrid integrated optical switch is fabricated by uniformly cladding few‐layer MoS 2 on the surface of inverse‐designed region. That is demonstrated to enhance the nonlinear optical response of device efficiently and achieve more excellent switching capability at high power.