Fig. 7: Enhanced coherent light-matter interaction and room-temperature quantum yield of a realistic hybrid CEP cavity.

a Schematic diagram of a hybrid CEP cavity based on WGM microdisk. A gold dimer consisting of two nanorods is placed on the top of WGM cavity, with a QE in the gap center and aligned matching the polarization of dipolar plasmonic mode. The radius of nanorods is 40 nm. Other geometry parameters are indicated in the figure. LDOS can by tuned by adjusting the edge-to-edge separation \(s\) between the cavity and the waveguide and the distance \(L\) between the cavity-waveguide junction and the mirror. The width of waveguide is 400 nm. The orange color illustrates the field profiles for \(\phi ={{{{{\rm{\pi }}}}}}\) and \({\omega }_{c}=1.462{{{{{\rm{eV}}}}}}\) obtained from electromagnetic simulation. b LDOS of the physical realization shown in (a) for various \(s\) obtained from electromagnetic simulations. The dashed lines with the same color plot the corresponding analytical results given by the quantized few-mode model [Eqs. (9)–(11)]. c Temporal dynamics of initially excited QE with a dipole moment \(\mu =48\) Debye for various LDOS shown (b). The inset shows the logarithmic plot of QE population. d Room-temperature quantum yield \(\eta\) of hybrid CEP cavity as the function of \({Q}_{c}\) and \({\kappa }_{c}/{\kappa }_{i}\). \({\eta }_{0}\) denotes the quantum yield of hybrid cavity without CEP. The red star indicates \({Q}_{c}\) and \({\kappa }_{c}/{\kappa }_{i}\) of WGM modes with frequency \({\omega }_{c}=2.246{{{{{\rm{eV}}}}}}\). Other parameters are \({g}_{1}=-11{{{{{\rm{meV}}}}}}\), \({g}_{a}=23.6{{{{{\rm{meV}}}}}}\), \({g}_{c}=0.171{{{{{\rm{meV}}}}}}\) and \({\gamma }_{{{{{{\rm{p}}}}}}}=30{{{{{\rm{meV}}}}}}\). e Room-temperature quantum yield \(\eta\) versus \({g}_{1}\) for various \({Q}_{c}\). The frequencies and decay rates of uncoupled gold dimer and WGM cavity are provided in the text. The dashed lines represent the quantum yield obtained by numerically calculating the expectation values of two operators using QuTip⁸³. f Room-temperature quantum yield \(\eta\) for various \({g}_{1}\). The parameters are \(\kappa ={\omega }_{c}/{10}^{4}\) and \({\kappa }_{c}={10}^{2}{\kappa }_{i}\). Other parameters are the same as (d).