Single layer graphene possessing anomalous dispersion with exotic microwave transmission and dielectric properties.

The present study aims to experimentally deduce the transmission and dielectric properties of CVD-grown single layer graphene transferred on glass and quartz substrates in wide frequency range from 100 MHz to 10 GHz. First, structural properties of graphene layer have been probed by Raman spectroscopy and then a simple and straightforward de-embedding method based on the propagation constants is adopted to deduce the effective relative permittivity of graphene layer. The graphene layer deposited on the substrate is found to exhibit higher absorption than the bare glass as well as quartz substrate in range of 2–10 GHz. The phase and group velocities have been determined and found to be in well agreement with values obtained by using the standard de-embedding method based on ABCD parameters. In both cases, graphene on glass and quartz, the maximum values of phase velocity are found to be ∼8.57 × 10 7 m/s at 4.12 GHz and ∼9.13 × 10 7 m/s at 4.52 GHz, respectively whereas the respective maximum group velocities for these materials are found to be ∼2.0 × 10 9 m/s and ∼1.9 × 10 9 m/s at 817 MHz. [ABSTRACT FROM AUTHOR]