Near-field control of optical bistability in a nanocavity

Dynamic control of the optical bistability of a nonlinear nanoresonator is shown to be achievable by modifying the resonance of the optical cavity with a dielectric near-field tip. It is experimentally demonstrated that the operating regime of the nanocavity can be switched between monostable and bistable regimes. Finally, an analytical model is proposed which provides an adequate description of the properties of the whole nonlinear optomechanical system.

Figure 1

(Color online) Experimental transmission spectrum through a high-$Q$ $\left(\sim 25000\right)$ small-volume $\left[\sim 0.6{\left(\lambda /n\right)}^3\right]$ Fabry-Perot-like nanocavity. The inset shows a SEM image of the cavity. The FP model prediction of the cavity resonance is superimposed in dashed line.

Figure 2

(Color online) (a) Experimental transmission spectrum measured at maximum power $\left(2.4\mu \text{W}\right)$ through the Fabry-Perot-like nanocavity. The nonlinear Fabry-Perot model predictions of the spectrum are plotted in dashed line. The inset shows the evolution of the spectrum as a function of the injected power. (b) Experimental measurements and FP model predictions of the nanocavity hysteresis loops for few values of wavelength detuning $\delta$.

Figure 3

(Color online) (a) Experimental setup used to measure the nanocavity hysteresis loops for various tip-cavity distances $\left(h\right)$. Nanocavity hysteresis loops (b) measured and (c) predicted for various tip-cavity distances recorded at a constant detuning $\left(\delta =300\text{pm}\right)$. (d) Schematic illustration of the bistable domain translation due to the tip-cavity interaction at a constant operating wavelength $\left({\lambda }_{\text{w}}\right)$.

Figure 4

(Color online) (a) Experimental and (b) simulated 2D diagrams of the hysteresis loop area variation as a function of the input power $\left(P_{\text{in}}\right)$ and of the tip height $\left(h\right)$ for a detuning of $\delta =300\text{pm}$. The representation allows a direct visualization of the $\left(P_{\text{in}},h\right)$ sets that correspond to monostable or bistable regimes.