Fig. 1. Experimental process, transmission electron microscope (TEM)/scanning electron microscope (SEM) image, X-ray diffraction (XRD) pattern, and electron density. (a) Experimental process of Au +CsPbBr3 QDs nanorod array laser device; (b) TEM/SEM picture of CsPbBr3 QDs, top view of nanorods array and cross section; (c) XRD patterns of Au+CsPbBr3 and CsPbBr3; (d) electron density with power ON and OFF at surface.

Fig. 2. Absorption, emission, and simulation of hot-e laser device. (a) Absorption spectrum of Au, CsPbBr3, Au+CsPbBr3 (ON), Au+CsPbBr3 (OFF) at the same pump with 5  kW cm−2 and 1 mA; (b) absorption spectrum of Au+CsPbBr3 (ON) at the different pump; (c) comparison of electroluminescence (EL), photoluminescence (PL), and electro-photoluminescence (EPL) in terms of CsPbBr3; (d) comparison of EL and PL in terms of Au+CsPbBr3; (e) lasing emission of the Au+CsPbBr3 device in the EPL pump under 5  kW cm−2 and 1 mA; (f) relationship between pump current and peak linewidth; (g) lasing emission of the Au+CsPbBr3 device in the EPL pump, the inset picture is the photo lasing from the device; (h) simulation of lasing process with different pump conditions in the size range −1.5–1.5  μm; (i) relationship between pump current and peak intensity; (j) L-L curve and the linewidth of the emission peak as a function of pumping power.

Fig. 3. TA and QE information in the Au+CsPbBr3 EPL device. (a) Polarization analysis of three-dimensional metal nanostructures; (b) extinction spectrum of metal nanostructures measured as TM-polarized light is normal incidence; (c) TA data recorded with the LSP wavelength of 406 nm with device OFF; (d) TA data recorded with the LSP wavelength of 406 nm with device ON; (e) TA dynamics at the wavelength 406 nm with device ON and OFF; (f) simulation of single Au+CsPbBr3 nanorod with TM mode; (g) QEs of HEG and HET of the device OFF; (h) QEs of HEG and HET of the device ON; (i) comparison of plasmon-induced hot electron generation efficiency of PL and EPL.

Fig. 4. PL spectrum of CsPbBr3 with and without Au under 808 nm/980 nm excitation. (a) Emission of hot electron transfer fluorescence from metal to CsPbBr3; (b) PL spectrum of CsPbBr3 without Au under 808 nm excitation; (c) PL spectrum of CsPbBr3 without Au under 980 nm excitation; (d) comparison of hot-e absorption and two-photon absorption.

Fig. 5. Hot electron transfer mechanism analysis of electrical and optical co-excitation pumping. (a) Electron changing in nanorod under optical pumping and optical and electrical pumping; (b) process of lasing emission with three gains; (c) microscope picture of lasing emission with WGM in the nanorod array; (d) lasing enhancement analysis in the energy level of Au-CsPbBr3 under two different pumping; (e) two modes of population inversion enhancement.