Echo wall microsphere molecular gas sensor based on graphene film

The invention belongs to the field of sensing, and particularly relates to an echo wall microsphere molecular gas sensor based on a graphene film. Sensing is carried out through beat frequency signalsof double combs in a microsphere cavity, a reference light path needed for establishing an interferometer is reduced, and therefore the size of the sensor is greatly simplified; the adopted microsphere cavity has an extremely high quality factor, so the mode line width is narrow, sensitivity of the sensor is greatly improved, the response time is only one thousandth of that of an electrochemicalgas sensor, and sensitivity can reach more than 10000 times of that of a traditional optical gas sensor and reaches a single molecular level; and meanwhile, two ends of the micro-nano optical fiber adopt joints of common single-mode optical fibers, so the micro-nano optical fiber can be conveniently accessed to the existing optical fiber communication network. The method is advantaged in that a basis is provided for a mini