“…Among the recently developed superlattice materials (Gong et al, 2012;Liu et al, 2016;Lin et al, 2018), the plasmonic superlattice membrane represents a new-generation of the thinnest possible two-dimensional metamaterials. Such a monolayered superlattice membrane consists of self-assembled metallic nanocrystals with closely packed nanoscopic structures and programmable multifunctions (Mueggenburg et al, 2007;Tao et al, 2007;Pang et al, 2008;Cheng et al, 2009;Dong et al, 2010Dong et al, , 2011Chen et al, 2011Chen et al, , 2013Liao et al, 2011), rendering a unique optical signature for considerable scope of applications such as nanoelectronics (Si et al, 2019), attachable SERS substrate (Chen et al, 2015), chiral sensors (Wu et al, 2018), to name a few. Since the concept of a "particle superlattice" was first introduced by Kotov et al (1994), substantial topdown and bottom-up strategies have been developed to build plasmonic superlattices, including the Langmuir-Blodgett technique (Tao et al, 2007), the droplet evaporation method (Mueggenburg et al, 2007;Chen et al, 2011), interface-based assembly (Pang et al, 2008;Liao et al, 2011), and acoustic levitation technique (Shi et al, 2019a).…”