• Special Issue
  • Perovskite Photonics
  • 10 Article (s)
Triple-cation perovskite solar cells for visible light communications|Spotlight on Optics
Natalie A. Mica, Rui Bian, Pavlos Manousiadis, Lethy K. Jagadamma, Iman Tavakkolnia, Harald Haas, Graham A. Turnbull, and Ifor D. W. Samuel
Hybrid perovskite materials are widely researched due to their high absorptivity, inexpensive synthesis, and promise in photovoltaic devices. These materials are also of interest as highly sensitive photodetectors. In this study, their potential for use in visible light communication is explored in a configuration that allows for simultaneous energy and data harvesting. Using a triple-cation material and appropriate device design, a new record data rate for perovskite photodetectors of 56 Mbps and power conversion efficiencies above 20% under white LED illumination are achieved. With this device design, the −3 dB bandwidth is increased by minimizing the dominating time constant of the system. This correlation between the bandwidth and time constant is proved using measurements of time-resolved photoluminescence, transient photovoltage, and device resistance.
Photonics Research
  • Publication Date: Jul. 14, 2020
  • Vol.8 Issue, 8 08000A16 (2020)
Influence of mixed organic cations on the nonlinear optical properties of lead tri-iodide perovskites
Xuanyu Zhang, Shuyu Xiao, Ruxue Li, Tingchao He, Guichuan Xing, and Rui Chen
Metal halide perovskite materials have been widely studied recently due to their excellent optoelectronic properties. Among these materials, organic-inorganic hybrid perovskites have attracted much attention because of their relatively soft framework, which makes them more suitable for nonlinear optical (NLO) applications. However, there is rare physical mechanism study on the coexistence of two-photon absorption (TPA) and saturable absorption (SA) in organic-inorganic hybrid perovskite materials. To clarify this issue, the NLO properties of mixed cation perovskite MA1-xFAxPbI3 [MA=CH3NH3,FA=CH(NH2)2, x=0, 0.2, 0.4, 0.6, and 0.8] thin films are investigated in this paper. Based on the nonlinear transmittance and femtosecond-transient absorption spectrum measurements, it is found that the MA1-xFAxPbI3 materials exhibit NLO behavior dependent on excitation intensity. The TPA coefficient of MA1-xFAxPbI3 decreases with the increase of formamidinium (FA) content, while the relevant saturable intensity increases. In addition, it is revealed that the linear absorption process from valence band 2 to valance band 1 still exists even under a very low excitation intensity. With the increase of excitation intensity, the light transmittance at 1300 nm decreases first and then increases sharply, which also supports the explanation for the coexistence of TPA and SA. It is expected that our findings will promote the application of perovskite materials in nonlinear optoelectronic devices.
Photonics Research
  • Publication Date: Aug. 17, 2020
  • Vol.8 Issue, 9 09000A25 (2020)
Mode selection and high-quality upconversion lasing from perovskite CsPb2Br5 microplates
Zhengzheng Liu, Chunwei Wang, Zhiping Hu, Juan Du, Jie Yang, Zeyu Zhang, Tongchao Shi, Weimin Liu, Xiaosheng Tang, and Yuxin Leng
In recent years, halide perovskite nanostructures have had great advances and have opened up a bright future for micro/nanolasers. However, upconversion lasing by two-photon excitation with mode selection and high quality factor in one device is still rarely reported. Herein, two lasing modes are demonstrated in the all-inorganic perovskite CsPb2Br5 microplates with subwavelength thickness and uniform square shape. The net optical gain is quickly established in less than 1 ps and persists more than 30 ps, revealed by ultrafast transient absorption spectroscopy. The temperature-dependent low-threshold amplified spontaneous emission confirms the net gain for stimulated emission with a high characteristic temperature of 403 K, far surpassing the all-inorganic CsPbBr3 semiconductor gain media. Remarkably, upconversion lasing based on two kinds of microcavity effects, Fabry–Pérot and whispering-gallery modes, from the microplates at room temperature is successfully achieved with a low threshold operating in multi- or single-mode, respectively. Surprisingly, the quality factor (~3551) is among the best values obtained from perovskite micro/nanoplate upconversion lasers without an external cavity. Moreover, the highly stable chromaticity with color drift only less than 0.1 nm also outbalances the all-inorganic CsPbBr3 ones. These superior performances of CsPb2Br5 microplate lasing with a facile solution synthesis procedure will offer a feasible structure to fabricate specific functionalities for high-performance frequency upconversion micro/nanoscale photonic integrated devices.
Photonics Research
  • Publication Date: Sep. 01, 2020
  • Vol.8 Issue, 9 09000A31 (2020)
Two-step solvent post-treatment on PTAA for highly efficient and stable inverted perovskite solar cells
Yang Li, Chao Liang, Gaopeng Wang, Jielei Li, Shi Chen, Shihe Yang, Guichuan Xing, and Hui Pan
Photonics Research
  • Publication Date: Sep. 18, 2020
  • Vol.8 Issue, 10 10000A39 (2020)
Exciton binding energy and effective mass of CsPbCl3: a magneto-optical study
Michal Baranowski, Paulina Plochocka, Rui Su, Laurent Legrand, Thierry Barisien, Frederick Bernardot, Qihura Xiong, Christophe Testelin, and Maria Chamarro
Photonics Research
  • Publication Date: Sep. 25, 2020
  • Vol.8 Issue, 10 10000A50 (2020)
Phase segregation in inorganic mixed-halide perovskites: from phenomena to mechanisms
Yutao Wang, Xavier Quintana, Jiyun Kim, Xinwei Guan, Long Hu, Chun-Ho Lin, Brendon Tyler Jones, Weijian Chen, Xiaoming Wen, Hanwei Gao, and Tom Wu
Halide perovskites, such as methylammonium lead halide perovskites (MAPbX3, X=I, Br, and Cl), are emerging as promising candidates for a wide range of optoelectronic applications, including solar cells, light-emitting diodes, and photodetectors, due to their superior optoelectronic properties. All-inorganic lead halide perovskites CsPbX3 are attracting a lot of attention because replacing the organic cations with Cs+ enhances the stability, and its halide-mixing derivatives offer broad bandgap tunability covering nearly the entire visible spectrum. However, there is evidence suggesting that the optical properties of mixed-halide perovskites are influenced by phase segregation under external stimuli, especially illumination, which may negatively impact the performance of optoelectronic devices. It is reported that the mixed-halide perovskites in forms of thin films and nanocrystals are segregated into a low-bandgap I-rich phase and a high-bandgap Br-rich phase. Herein, we present a critical review on the synthesis and basic properties of all-inorganic perovskites, phase-segregation phenomena, plausible mechanisms, and methods to mitigate phase segregation, providing insights on advancing mixed-halide perovskite optoelectronics with reliable performance.
Photonics Research
  • Publication Date: Oct. 30, 2020
  • Vol.8 Issue, 11 11000A56 (2020)
Cavity engineering of two-dimensional perovskites and inherent light-matter interaction|On the Cover
Shuai Zhang, Yangguang Zhong, Fan Yang, Qinxuan Cao, Wenna Du, Jianwei Shi, and Xinfeng Liu
Two-dimensional (2D) perovskites are hybrid layered materials in which the inorganic lattice of an octahedron is sandwiched by organic layers. They behave as a quantum-well structure exhibiting large exciton binding energy and high emission efficiency, which is excellent for photonic applications. Hence, the cavity modulation and cavity devices of 2D perovskites are widely investigated. In this review, we summarize the rich photophysics, synthetic methods of different cavity structures, and the cavity-based applications of 2D perovskites. We highlight the strong exciton–photon coupling and photonic lasing obtained in different cavity structures. In addition, functional optoelectronic devices using cavity structures of 2D perovskites are also reviewed.
Photonics Research
  • Publication Date: Oct. 30, 2020
  • Vol.8 Issue, 11 11000A72 (2020)
Engineering a light–matter strong coupling regime in perovskite-based plasmonic metasurface: quasi-bound state in the continuum and exceptional points
Leran Lu, Quynh Le-Van, Lydie Ferrier, Emmanuel Drouard, Christian Seassal, and Hai Son Nguyen
We present theoretically the formation of exciton&ndash;photon polaritons and exciton-surface plasmon polaritons in a perovskite-based subwavelength lattice on the metallic plane. It is shown that the later polaritons will be achieved as the perovskite layer is ultra-thin (<50 nm), while the co-existence of both polaritons will dominate, as the thickness of the perovskite metasurface approaches wavelength-scale. In the two cases, the lower polaritonic branches consist of dark and bright modes corresponding to infinite and finite radiative quality factors, respectively. Another salient property in this work is that it allows one to obtain exceptional points (EPs) in momentum space with a four-fold enhancement of local density of states through engineering the perovskite metasurface. Our findings show that the perovskite metasurface is an attractive and rich platform to make polaritonic devices, even with the presence of a lossy metallic layer.
Photonics Research
  • Publication Date: Nov. 12, 2020
  • Vol.8 Issue, 12 12000A91 (2020)

Recent progress in photonics research has led to the discovery of novel optical materials, in which metallic halide perovskites plays a large role for semiconductor photonics. Owing to their stunning optical properties, perovskites have been widely considered as promising platforms for the manipulation of photons in free space/matter based on bulk and low-dimensional systems. Recently, a series of significant efforts and breakthroughs in perovskite photonics have been reported by institutions and companies around the world, opening a bright path to demonstrating next-generation excellent-performance, low-consumption optoelectronic devices.

 

On the Cover for this virtual special issue

Large area perovskite solar cells: the way for application. See Yang Zhao et al., page 070000A1.