SCIENTECH INC — Department of Defense STTR Phase I: HR001121S0007-29

Description

This work seeks to develop a receiver for high-power wireless energy transmission based on thermal-to-electric energy conversion using solid-state pyroelectric materials, which can convert time-varying temperature fluctuations to electricity, coupled with a modulated radiation source. The proposed receiver relies on a multilayer device architecture comprising nanometer-thick pyroelectric films that can achieve electric fields >100 kV cm-1 and enable thermal cycling at rates >100 Hz leading to high power density. In order to maximize optical-to-electrical energy conversion efficiency and realize high-frequency thermal-electrical cycles, the receiver includes a front interface that maximizes absorption of free-space laser radiation into surface plasmon polaritons that strongly couple with optical phonons for efficient device heating, and a back interface comprising a graphene layer coupled with plasmonic structures that allows electric-field control of thermal emission. By combining electrothermal control of polarization in pyroelectric materials and control of emissivity in plasmonic structures, we will develop platforms to investigate the interaction of electro-optic, optothermal and electrothermal transport processes and enable next-generation power transmission, energy generation and sensing technologies.