Detection of finite-frequency photoassisted shot noise with a resonant circuit

Photoassisted transport through a mesoscopic conductor occurs when an oscillatory (ac) voltage is superposed to the constant (dc) bias which is imposed on this conductor. Of particular interest is the photoassisted shot noise, which has been investigated theoretically and experimentally for several types of samples. For dc-biased conductors, a detection scheme for finite-frequency noise using a dissipative resonant circuit, which is inductively coupled to the mesoscopic device, was developed recently. We argue that the detection of the finite-frequency photoassisted shot noise can be achieved with the same setup, despite the fact that time translational invariance is absent here. We show that a measure of the photoassisted shot noise can be obtained through the charge correlator associated with the resonant circuit, where the latter is averaged over the ac drive frequency. We test our predictions for a point contact placed in the fractional quantum-Hall-effect regime, for the case of weak backscattering. The Keldysh elements of the photoassisted noise correlator are computed. For simple Laughlin fractions, the measured photoassisted shot noise displays peaks at the frequency corresponding to the dc bias voltage, as well as satellite peaks separated by the ac drive frequency.