Optical bistability in the plexcitonic Ag-CuCl nanowire

Optical bistability (OB) of plexcitonic Ag-CuCl nanowires (ACNWs) is investigated based on the quasi-static theory. It is found that the strong couplings between the plasmon resonance of inner Ag nanowire and the exciton resonance of outer CuCl shell result in two new plexcitonic modes, which can induce the OBs and hence the two OB regions. Furthermore, the initial wavelengths of the OBs in the ACNW show slight red shifts compared to the resonance wavelengths of the plexcitonic modes. In addition, we find that the plexcitonic modes-induced OBs in the ACNW can be modulated by varying the thickness of outer shell.