Fig. 8: Photoluminescence from defect-bound excitons in phosphorene.
From: Photoluminescence as a probe of phosphorene properties
a Measured PL spectra of monolayer phosphorene samples produced by different methods: sample 1 exfoliated monolayer phosphorene (1), monolayer phosphorene with PxOy capping layer fabricated by oxygen plasma etching (2), and monolayer phosphorene with PxOy capping layer fabricated by oxygen plasma etching, but with overetching by oxygen plasma (3). The figure was reproduced with permission from ref. 61. b Measured PL spectra of the monolayer phosphorene on PECVD oxide/Au (blue) and thermal oxide/Si (red) substrates. The measured PL spectra from the substrate background are also plotted for comparison. c Integrated PL of the low-energy X peak. The sublinear growth of integrated PL with the increased excitation power (α = 0.72), indicating that the X peak at ≈920 nm is from localized excitons. The figure was reproduced with permission from ref. 110. d Measured PL spectra at various temperatures for phosphorene 3L sample. e Schematic diagram showing the position of localized (low energy) and free (high energy) excitons at low temperature and elevated temperatures. Measured f peak position, g peak intensity, and h FWHM of PL peaks A and X as a function of temperature in 3L phosphorene. The figure was reproduced with permission from ref. 64.
