▎ 摘　　要

NOVELTY - The sensor has a sapphire layer (2) set on a silicon substrate (1). A surface of the sapphire layer is provided with a sample area (6) for containing a sample to-be-tested. The sample area is provided with a nanometer graphene strip waveguide (3). A first graphene resonator cavity (4) is directly connected with the nanometer graphene strip waveguide. A second graphene resonator cavity (5) is indirectly connected with the nanometer graphene strip waveguide through the first graphene resonant cavity, where the nanometer graphene strip waveguide, the first graphene resonant cavity and the second Graphene resonant cavity are made of single- layer graphene. USE - PIT effect based graphene refractive index sensor. ADVANTAGE - The sensor has small size, high sensitivity, wide testing range and better application prospect detection of the biological macromolecule and chemical substances. DESCRIPTION OF DRAWING(S) - The drawing shows a front view of a PIT effect based graphene refractive index sensor. Silicon substrate (1) Sapphire layer (2) Nanometer graphene strip waveguide (3) Graphene resonator cavities (4,5) Sample area (6)