Tze-Chien Sum

This book explores the incorporation of plasmonic nanostructures into organic solar cells, which offers an attractive light trapping and absorption approach to enhance power conversion efficiencies. The authors review the latest advances in the field and discuss the characterization of these hybrid devices using a combination of optical and electrical probes. Transient optical spectroscopies such as transient absorption and transient photoluminescence spectroscopy offer powerful tools for observing charge carrier dynamics in plasmonic organic solar cells. In conjunction with device electrical characterizations, they provide unambiguous proof of the effect of the plasmonic nanostructures on the solar cells’ performance. However, there have been a number of controversies over the effects of such integration – where both enhanced and decreased performance have been reported. Importantly, the new insights into the photophysics and charge dynamics of plasmonic organic solar cells that these spectroscopy methods yield could be used to resolve these controversies and provide clear guidelines for device design and fabrication.

This book highlights the rapidly emerging field of solution-processed halide perovskite lasers. These amazing materials not only possess exceptional photovoltaic properties, but are also outstanding optical gain media. Halide perovskites are the latest member of solution-processed optical gain media, joining organics and traditional semiconductor colloidal quantum dots. Amplified spontaneous emission and lasing have been demonstrated in various halide perovskite configurations and nanostructures with wavelengths tunable over the visible and infrared wavelengths (400–1000 nm). This book provides comprehensive information on perovskite lasing, starting with some fundamentals of lasers and their basic operating principles. Unambiguous methods for identifying lasing light emission are presented, while the basic optoelectronic properties of perovskite materials are also discussed, with an emphasis on their photophysics, using ultrafast optical spectroscopy techniques. The viabilityof perovskites as a gain media within a suitable resonator, as well as the characterization methods for optical gain, are highlighted. The book closes with a discussion on the remaining challenges (such as electrical driven lasing and material stabilities) that need to be tackled, and the future of this new family of lasers.