Fig. 4: Lasing characteristics of VCSEL and CBR laser.
From: Low-threshold surface-emitting colloidal quantum-dot circular Bragg laser array
a PL spectra of CQDs in and out of CBR under low pumping intensity. b PL spectra of CQD CBR laser under different pumping intensities from 10 μJ cm−2 to 22 μJ cm−2. The inset photographs show the CBR laser array operating below and above its lasing threshold. c Pumping fluence-dependent emission intensity and FWHM of CQD CBR laser. d Emission spectrum of CQD CBR laser under pumping fluence of 25 μJ cm−2 and its Gaussian fitting. e Pumping fluence-dependent emission intensity and FWHM of CQD VCSEL. f Emission spectrum of CQD VCSEL under pumping fluence of 100 μJ cm−2 and its Gaussian fitting
