Sensing gas through coupling effect of quasi-PT-symmetry resonators

In order to detect all toxic gases with high sensitivity in low concentration range, a quasi-PT-symmetry resonator coupling system is proposed to design the sensor with the advantages of simple structure, low cost, high sensitivity in low concentration, and direct detection. The gas sensor uses coupling effect as the basis to build the one-to-one correspondence relationship between the transmittance and the gas concentration in the air, and the transmittance (T) is proportional to the light power that can be transformed into electric current through photoelectric sensors, and the results can be read directly through the change of light current. The maximum sensitivities of −ΔT/(TΔp) are 668 and 76.6 for Benzene and for Methane, respectively. The high sensitivity just occurs in the low concentration range. Such a result is good for the practical detection environment.