Figure 3
From: Intrinsically p-type cuprous iodide semiconductor for hybrid light-emitting diodes
Optically pumped continuous wave (CW) lasing of the CuI epitaxial layer grown on sapphire with the vertical cavity at cryogenic temperature is observed. The lasing takes place at 10 K in a sample with a vertical cavity formed by the Ag coating on top of the CuI layer with a thickness of 1.15 \(\mu m\) and the bottom of the sapphire substrate. The CW pumped lasing peak centered at around 412 nm with a narrow central mode is visible in this figure. The PL spectrum is also shown for comparison. The insert shows the log-log plot of the emission intensity as a function of the excitation power density denoted by the percentage of the neutral density (ND) filter employed to control the input power. We estimate the threshold power density to be approximately 250 W/cm2.
