Rapid large-scale fabrication of metasurfaces with complex unit cells

A method of fabricating a metasurface, the method comprising:

• providing a photoresist film disposed on a substrate;
• exposing the photoresist film with a first interference pattern, the first interference pattern having a first period and a first exposure energy;
• exposing the photoresist film with a second interference pattern, the second interference pattern having a second period and a second exposure energy;
• rotating the substrate;
• exposing the photoresist film with a third interference pattern, the third interference pattern having a third period and a third exposure energy;
• exposing the photoresist film with a fourth interference pattern, the fourth interference pattern having a fourth period and a fourth exposure energy;
• and
• generating a two-dimensional periodic metasurface,
• wherein the first interference pattern and the second interference pattern are disposed along the same dimension;
• wherein the third interference pattern and the fourth interference pattern are disposed along the same dimension
• wherein the first period and the second period have a least common multiple (LCM) such that a final metasurface period is larger than either of the first period and the second period;
• and
• wherein the third period and the fourth period have a least common multiple (LCM) such that a final metasurface period is larger than either of the third period and the fourth period.