Room-Temperature Continuous-Wave Microcavity Lasers from Solution-Processed Smooth Quasi-2D Perovskite Films with Low Thresholds

Abstract

Continuous-wave (CW) lasing in quasi-two-dimensional (2D) perovskitebased distributed feedback cavities has been achieved at room temperature; however, CW microcavity lasers comprising distributed Bragg reflectors (DBRs) have rarely been prepared using solution-processed quasi-2D perovskite films because the roughness of perovskite films significantly increases intersurface scattering loss in the microcavity. Herein, high-quality spincoated quasi-2D perovskite gain films were prepared using an antisolvent to reduce roughness. The highly reflective top DBR mirrors were deposited via room-temperature ebeam evaporation to protect the perovskite gain layer. Lasing emission of the prepared quasi-2D perovskite microcavity lasers under CW optical pumping was clearly observed at room temperature, featuring a low threshold of ∼1.4 W cm −2 and beam divergence of ∼3.5°. It was concluded that these lasers originated from weakly coupled excitons. These results elucidate the importance of controlling the roughness of quasi-2D films to achieve CW lasing, thus facilitating the design of electrically pumped perovskite microcavity lasers.

High-Quality Solution-Processed Quasi-2D Perovskite for Low-Threshold Lasers

“…The RMS roughness of films 1, 2, 3, 4, and 5 are 2.9 1.9, 2.3, 3.4, and 4.1 nm, respectively, as summarized in Figure f. All the above characterization suggests that the morphology and microscopic structures of P2F8 film can be optimized through the engineered spin coating process, which is of significant importance for the realization of CW lasers and plasmonic lasers. , …”

“…All the above characterization suggests that the morphology and microscopic structures of P2F8 film can be optimized through the engineered spin coating process, which is of significant importance for the realization of CW lasers and plasmonic lasers. 44,45 PL spectroscopy and laser gain properties of these quasi-2D perovskite thin films are investigated using a 343 nm microscopic femtosecond laser. As shown in Figure 5a, the PL spectrum of film 2 at low pump densities (<11 μJ/cm 2 ) shows a central wavelength of 547 nm and a fwhm width of 26.75 nm corresponding to a spontaneous emission.…”

Advances in Colloidal Quantum Dot Laser Diodes

“…In this case, researchers need to explore new methods to address these issues. Gao et al's research has shown that interface engineering can effectively reduce optical losses caused by interface states [68], thereby improving the quality factor and laser characteristics of microcavities (Figure 7).…”

Improved Photoluminescence, Electroluminescence, and Laser Characteristics of 1-Naphthylmethylamine-Based Quasi-Two-Dimensional Perovskite Films at Lower Temperatures

“…16 Gao et al obtained room-temperature continuouswave (CW) lasing from quasi-two-dimensional (quasi-2D) perovskite films with a low threshold of 1.4 W cm −2 . 17 Kim et al demonstrated that methylammonium lead iodide (CH 3 NH 3 PbI 3 ) LEDs with a second-order distributed feedback (DFB) structure exhibiting optical laser thresholds as low as ≈6 μJ cm −2 at room temperature. 18 However, lasing from perovskites under electrical pumping has never been reported to date.…”