Temperature-Dependent Amplified Spontaneous Emission in CsPbBr<sub>3</sub> Thin Films Deposited by Single-Step RF-Magnetron Sputtering
Giovanni Morello,
Stefania Milanese,
Maria Luisa De Giorgi,
Nicola Calisi,
Stefano Caporali,
Francesco Biccari,
Naomi Falsini,
Anna Vinattieri,
Marco Anni
Affiliations
Giovanni Morello
CNR-IMM, Institute for Microelectronic and Microsystems Unit of Lecce, Via per Monteroni, 73100 Lecce, Italy
Stefania Milanese
Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento, Via per Arnesano, 73100 Lecce, Italy
Maria Luisa De Giorgi
Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento, Via per Arnesano, 73100 Lecce, Italy
Nicola Calisi
Department of Industrial Engineering, University of Florence, Via di S. Marta 3, 50139 Firenze, Italy
Stefano Caporali
Department of Industrial Engineering, University of Florence, Via di S. Marta 3, 50139 Firenze, Italy
Francesco Biccari
Department of Physics and Astronomy and LENS, University of Florence, Via G. Sansone1, 50125 Sesto Fiorentino (FI), Italy
Naomi Falsini
Nuclear Safety, Security and Sustainability Division, Fusion and Technology for Nuclear Safety and Security Department, Italian National Agency for New Technologies, Energy and Sustainable Economic Development (ENEA), Via Martiri di Monte Sole 4, 40129 Bologna, Italy
Anna Vinattieri
Department of Physics and Astronomy and LENS, University of Florence, Via G. Sansone1, 50125 Sesto Fiorentino (FI), Italy
Marco Anni
Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento, Via per Arnesano, 73100 Lecce, Italy
Due to their high optical efficiency, low-cost fabrication and wide variety in composition and bandgap, halide perovskites are recognized nowadays as real contenders for the development of the next generation of optoelectronic devices, which, among others, often require high quality over large areas which is readily attainable by vacuum deposition. Here, we report the amplified spontaneous emission (ASE) properties of two CsPbBr3 films obtained by single-step RF-magnetron sputtering from a target containing precursors with variable compositions. Both the samples show ASE over a broad range of temperatures from 10 K up to 270 K. The ASE threshold results strongly temperature dependent, with the best performance occurring at about 50 K (down to 100 µJ/cm2), whereas at higher temperatures, there is evidence of thermally induced optical quenching. The observed temperature dependence is consistent with exciton detrapping up to about 50 K. At higher temperatures, progressive free exciton dissociation favors higher carrier mobility and increases trapping at defect states with consequent emission reduction and increased thresholds. The reported results open the way for effective large-area, high quality, organic solution-free deposited perovskite thin films for optoelectronic applications, with a remarkable capability to finely tune their physical properties.
