| Popis: |
Evidence is presented for a second condensed phase of excitons in unstressed, high-purity Ge, based on a simple plasma line-shape analysis. Above the critical temperature for electron-hole liquid condensation (T c ≃7 K), time-resolved photoluminescence spectra can be fit with an electron-hole plasma component with nondecaying density, implying spatial condensation into droplets. Shortly after the excitation source is switched of, all successive luminescence spectra are fit with a constant-density electron-hole plasma line shape plus contributions from free excitons and excitonic complexes |
