Fig. 2: Optomechanically induced transparency (OMIT) in the Coulomb blockade regime.
From: Quantum capacitance mediated carbon nanotube optomechanics
a Frequency scheme and b detection setup of an OMIT measurement. A strong drive signal at ωd = ωc − ωm pumps the microwave cavity; the cavity transmission near the cavity resonance ωc is characterized using a superimposed weak probe signal ωp from a vector network analyzer (VNA). Device parameters are: ωc ≃ 2π ⋅ 5.74 GHz, κc = 2π ⋅ 11.6 MHz, ωm ≃ 2π ⋅ 502.5 MHz. c–e Probe signal power transmission \({|{S}_{21}({\omega }_{{\rm{p}}})|}^{2}\) for three different choices of cavity drive frequency ωd, at ωd = ωc − ωm (c) and slightly detuned (d, e). The gate voltage Vg = −1.1855 V is fixed on the flank of a sharp Coulomb oscillation of conductance; Vsd = 0. f Probe signal transmission as in c–e, now for a fixed cavity drive frequency ωd = 2π ⋅ 5.23989 GHz and varied gate voltage Vg across a Coulomb oscillation. The depth of the OMIT feature allows the evaluation of the optomechanical coupling g(Vg) at each gate voltage value. g Optomechanical coupling g(Vg) (left axis) and corresponding single photon coupling \({g}_{0}({V}_{{\rm{g}}})=g({V}_{{\rm{g}}})/\sqrt{{n}_{{\rm{c}}}}\) (right axis), extracted from the data of f; nc = 67,500. Error bars indicate the standard error of the fit result.
