First steps towards a chipless, passive THz-based epidermal electronics concept

This contribution rethinks epidermal electronic concepts by introducing a passive, chipless and wireless approach for skin-based health information detection. The idea is based on the sensitivity of the graphene electrochemical potential to chemical or electrical potential changes at the interface of the thin film and the impact of this on the graphene reflection properties in the THz range. This feature has the potential to enable contactless information readout for future applications, while at the same time significantly simplifying epidermal electronics patches and thus mitigating current technology limitations. In this contribution a proof of principle experiment based on a dual gate electrochemical graphene transistor structure is discussed, to demonstrate the tuneability of the graphene electrochemical potential as a prerequisite for our concept. THz time domain spectroscopy is then used to demonstrate he impact of this electrochemical potential variation on the graphene reflection properties between 100GHz and 1.5THz, proving the feasibility of our concept.