Giant nonlieaner optical modulation based on layered materials beyond EFISH

The efficient modulation of optical signals is central to communication and computing, the key in emerging data science revolution. Towards the realization of on-chip nonlinear optical applications such as on-demand nonlinear optical sources and neutral network, electrical-field-induced second harmonic generation (EFISH) dominates the development because of its ubiquitous presence in different material systems. However, its third order nature grinds itself to be a weak and inefficient process. A new mechanism that directly controlling second-order electric susceptibility to realize efficient nonlinear tunability is on demand. We report an electrically controlled new strategy to achieve giant and broadband modulation of second-order optical nonlinearities with an ultra-large modulation strength as well as efficiency. This demonstration will have a profound impact to optical communication and photonic computation.