We present the findings of the excitonic normal-mode coupling (NMC) with the single silicon quantum well (SQW) embedded in a 1λ silicon microcavity that exhibits the high efficient photoluminescence of bound excitons at the iron-boron pair and the erbium-related centers inserted in SQW.
The n- type Si (100) wafers preliminary doped with iron and erbium were oxidized at 1150 C in dry oxygen containing CCl4 vapors. Short-time boron doping was done from the gas phase under fine surface injection of both self-interstitials and vacancies into the window, which was cut in the oxide overlayer after preparing a mask and performing the subsequent photolithography. The four-point probe under layer-by-layer etching and SIMS measurements allowed the depth of the p+ boron diffusion profile, 8 nm. The CR angular dependencies have shown that the profile prepared contains the low density p-type SQW confined by the delta barriers heavily doped with boron. Besides, the STM images have demonstrated that this single SQW is incorporated into the microcavity system of the fractal type formed by the microdefects of the self-interstitials type. These silicon microcavities are revealed by the angle-resolved transmission spectra that exhibit the NMC regime with a single SQW in the spectral range of the Rabi splitting at T=300 K. Moreover, the bound excitons at a single point defect appeared to cause giant exchange splitting in the absence of the external magnetic field that is created by strong coupling between d or f-electron states of the center and the s-p electronic states of the host SQW. This strong sp-d or sp-f mixing is revealed by the angle-resolved photoluminescence and absorption that seem to be the ODMR spectra in zero magnetic fields under the NMC conditions, because the EPR frequency is able to be selected from the GHz range generated by SQW being in self-agreement the exchange splitting value. The EPR frequency values, 87 GHz and 200 GHz, which allow the transmission spectra under the ODMR conditions appeared to correlate respectively with the line splitting value of the bound exciton at the trigonal iron-boron pair and trigonal erbium-related center.
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