Neutralization Of Positively Charged Excitonic State In Single Inas Quantum Dot By Si Delta Doping

Positively charged excitonic state in single InAs quantum dot ( QD) has been neutralized by Si delta doping and the optical properties of the fabricated samples are characterized by micro-photoluminescence measurements (mu-PL) at low temperature. An InAs QD sample having dominant emissions from positively charged excitonic states is prepared for a reference. By optimizing Si delta doping conditions, positively charged QDs are neutralized successfully and distinctive emissions from neutral exciton and biexciton from single QDs are achieved. For excessive doping condition, mu-PL spectra show optical degradation of lowering of peak intensity and broadening of peak width as doping concentration increases.