Figure 1

(Color online) Temperature-dependent $\mu \text{PL}$ spectra of a $1.6\mu \text{m}$ diameter micropillar (a) at zero magnetic field and (b) at 3 T. The fundamental pillar cavity mode is split into two components $C_1$ and $C_2$. At $B=0$ strong coupling between the photon modes and the nearly degenerate quantum dot exciton modes $X_{1,2}$ is identified by the avoided crossing of the associated lines with a mode’s energy splitting of $86\mu \text{eV}$. Coupling between the Zeeman split exciton lines ($X_1$ and $X_2$) and the cavity modes at $B=3\text{T}$ is seen in panel (b) and gives two interaction regions marked by arrows.Reuse & Permissions

Figure 2

(Color online) Schematic illustration of the energy dependences of the two excitons and the two cavity modes as a function of magnetic field at fixed temperature without light-matter coupling. (a) Two degenerate cylindrical cavity modes and two Zeeman split bright excitons in cylindrically symmetric QDs. (b) An asymmetry of the micropillar splits the two cavity modes by $\alpha$ and an asymmetry of the QD splits the bright exciton by $\beta$. At zero magnetic field, one observes two linearly polarized exciton modes separated by the fine-structure splitting. Increasing magnetic field gives rise to circularly polarization of the excitons.Reuse & Permissions

Figure 3

(Color online) Energy dispersion and emission linewidths of the coupled modes at $B=3\text{T}$ as functions of temperature. (a) Experimental values (bullets) obtained by Lorentzian line-shape fitting of the data in Fig. 1b and calculated energy positions for $g=38\mu \text{eV}$ (solid lines). The black dashed lines indicate the peak energies for noninteracting modes, i.e., for $g=0$. The physical meaning of parameters $\alpha$ and $\tilde{\beta }$ in Eq. (1) is indicated. (b) Corresponding emission mode linewidths. In the interaction regions denoted by shaded areas, a pronounced mixing of three (two “cavitylike” and one “exciton-like”) modes occurs as a signature of the coherent light-matter interaction. The black dashed line indicates the expected value of linewidth crossings $\left({\Gamma }_C+{\Gamma }_X\right)/2=64\mu \text{eV}$ for strong coupling of one exciton and a single photonic mode. The shift of the crossing points toward larger energies (at temperatures marked by arrows) indicates considerable involvement of the second photonic mode in the region of interaction.Reuse & Permissions