Figure 1

Analogy between a network of coupled optical cavities and a physical network where the excitation is carried by electrons, such as light-harvesting complexes. (a) The single site of the network is analogous to a single optical cavity. (b) The electronic excitation is represented by the presence of a single photon in the corresponding optical cavity. (c) The transfer of the excitation between two interacting sites is analogous to the transfer of the single-photon between two adjacent coupled cavities.Reuse & Permissions

Figure 2

Quantum simulation of noise-assisted excitation transfer through a network of coupled optical cavities. (a) Simplified scheme of a four-site fully connected network. The excitation is injected at site $1$, and exits from the network by coupling of site $2$ with the output sink. (b) Equivalent network of four coupled cavities. The excitation is given by a single-photon pulse injected into cavity $1$. The right output mode of cavity $2$ is the output sink channel for the excitation.Reuse & Permissions

Figure 3

Scheme of all coupling, dissipation, and dephasing processes of the network. All sites are coupled with the network with $g_{\mathit{kj}}$ couplings, and undergo both a dephasing process, with rate $\gamma$, and internal losses, with rate ${\Gamma }_j$. Site 1: external losses are reduced with a feedback system. Site 2: external coupling with the sink. Sites 3 and 4: external losses are negligible with respect to internal losses (${\Gamma }_{\mathrm{out}}^j\ll {\Gamma }_j$).Reuse & Permissions

Figure 4

Experimental setup for the four-cavities optical network. The single photon in the input mode ${\mathbf{k}}_{\mathrm{in}}$ is injected into the network at site $1$. The successful transfer of the excitation in the network is given by the detection of the single photon on mode ${\mathbf{k}}_{\det }$. The coupling coefficients between cavities can be changed by varying the transmittivity and the reflectivity of the beam-splitter (BS). The feedback system to reduce the dissipation rate ${\Gamma }_{\mathrm{out}}^1$ from site $1$ exploits the polarization degree of freedom of the photon as described in the text. Inset (a): Sketch of an active phase stabilization apparatus. An auxiliary laser is injected and extracted into the network by two dichroic mirrors (DM). The measurement on the auxiliary laser is used to drive a piezoelectric system which stabilizes the cavity length. Inset (b): Introduction of dephasing rate by modulation of the index of refraction through an electro-optical crystal.Reuse & Permissions

Figure 5

Site $1$ population behavior and transfer efficiency vs time (in $\mathrm{ns}$) for the optical cavity network for the noiseless (continuous line) and noisy (dashed line) case. The photon transmission is significantly enhanced by the presence of dephasing. The error bars are calculated considering a $20\%$ static disorder (${10}^3$ samples).Reuse & Permissions

Figure 6

Dependence of $p_{\mathrm{sink}}$ at a fixed time $t=20\hspace{0.5em}\mathrm{ns}$ as a function of the dephasing rate $\gamma$. These results show the remarkable robustness of this process, supporting the possibility that it could be experimentally observed.Reuse & Permissions

Figure 7

Degradation of entanglement between two photons (initially in a maximally entangled state), in which only one photon is sent to the network through cavity $1$. It is measured in terms of log-negativity between the ancilla photon and the photon leaving cavity $2$ (no detector).Reuse & Permissions