Vertically Aligned Few-Layered Graphene-Based Non-Cryogenic Bolometer

In this study, we report the photoresponse of vertically aligned few-layered graphene (VAG) upon infra-red (IR) irradiation at room temperature. Four probe measurements showed the current-voltage (I-V) characteristic of electrical switching during pulsed IR irradiation. The photoresponse reported here for VAG was significantly higher than that reported for carbon nanotube (CNT) samples. Our investigation shows that such a photoresponse arose solely from the bolometric effect, where the conductivity changed with temperature. The resistance magnitude of the VAGs increased two fold for each 6 degrees C increase in temperature. Also, the Thermal Coefficient of Resistance (TCR) in this region was 11%/K, which is the highest TCR value reported for any carbon nanomaterial.