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arXiv · 2007.04567

Ultra-sensitive Parity-Time Symmetry based Graphene FET (PTS-GFET) Sensors

Lu Ou·Shaolin Liao
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Abstract

A novel ultra-sensitive Parity-Time symmetry based Graphene FET (PTS-GFET) sensor is studied for gas concentration detection. The PTS-GFET sensor effectively integrates the sensitivity of the PT symmetry around its Exceptional Point (EP) and the tunability of the GFET conductance. The change of GFET conductance with the gas concentration can be brought back to the EP of the PTS-GFET by tuning the gate voltage on the GFET. Thus, the applied gate voltage indicates the gas concentration. The minimum detectable gas concentration has been derived and estimated based on the experimental data, which shows that PTS-GFET can detect gas concentration below 50 ppb.

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Lu Ou, Shaolin Liao. 2020-07-09. Ultra-sensitive Parity-Time Symmetry based Graphene FET (PTS-GFET) Sensors. https://arxiv.org/abs/2007.04567

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