Enhanced Exciton and Photon Confinement in Ruddlesden–Popper Perovskite Microplatelets for Highly Stable Low‐Threshold Polarized Lasing. Issue 23 (30th April 2018)

• Record Type: Journal Article
• Authors: Li, Mingjie; Wei, Qi; Muduli, Subas Kumar; Yantara, Natalia; Xu, Qiang; Mathews, Nripan; Mhaisalkar, Subodh G.; Xing, Guichuan; Sum, Tze Chien
• Is Part Of: Advanced materials. Volume 30:Issue 23(2018)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2018-04-30
• Subjects: exciton confinement -- high stability -- low‐threshold lasing -- photon confinement -- Ruddlesden–Popper perovskites; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adma.201707235
• Languages: English
• ISSNs: 0935-9648

Abstract

Abstract: At the heart of electrically driven semiconductors lasers lies their gain medium that typically comprises epitaxially grown double heterostuctures or multiple quantum wells. The simultaneous spatial confinement of charge carriers and photons afforded by the smaller bandgaps and higher refractive index of the active layers as compared to the cladding layers in these structures is essential for the optical‐gain enhancement favorable for device operation. Emulating these inorganic gain media, superb properties of highly stable low‐threshold (as low as ≈8 µJ cm −2 ) linearly polarized lasing from solution‐processed Ruddlesden–Popper (RP) perovskite microplatelets are realized. Detailed investigations using microarea transient spectroscopies together with finite‐difference time‐domain simulations validate that the mixed lower‐dimensional RP perovskites (functioning as cladding layers) within the microplatelets provide both enhanced exciton and photon confinement for the higher‐dimensional RP perovskites (functioning as the active gain media). Furthermore, structure–lasing‐threshold relationship (i.e., correlating the content of lower‐dimensional RP perovskites in a single microplatelet) vital for design and performance optimization is established. Dual‐wavelength lasing from these quasi‐2D RP perovskite microplatelets can also be achieved. These unique properties distinguish RP perovskite microplatelets as a new family of self‐assembled multilayer planar waveguide gain media favorable for developing efficient lasers. Abstract : A low‐threshold optically pumped solution‐processed Ruddlesden–Popper perovskite microplatelet laser that emits high‐stability linearly polarized emission is realized. The superb lasing properties are attributed to the mixed lower‐dimensional perovskite layers (acting as cladding layers) that provide both enhanced exciton and photon confinement for the higher‐dimensional perovskite layers (functioning as gain media).