I propose to develop novel metamaterial silicon half wave plates and antireflection coatings for use in cosmic microwave background observations. These new HWPs and AR coatings will have lower loss and broader bandwidth than conventional sapphire hwps or other AR coatings. These coatings will designed using computer simulations including commercial high frequency finite element analysis software. They will be fabricated using our custom three axis dicing saw here at the University of Michigan, and they will be deployed in the field on ACTPol and the PIPER balloon. Together, these new technologies will allow for unambiguous detection of primordial gravitational waves.