Fig. 6From: Terahertz spectroscopy in biomedical field: a review on signal-to-noise ratio improvementConceptual view of the PIT-sensor based on graphene micro-ribbon (GMR). The electromagnetic field is mainly concentrated at the edges of GMR, when excited by a THz wave, leading to the enhanced interaction between THz wave and the analyte. The tunability of the PIT sensor is achieved by changing the bias voltages (V1 and V2) applied on the two sets of GMR arrays [41]Back to article page