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Hybrid metal halide perovskites (MHPs) have shown remarkable optoelectronic properties as well as facile and cost-effective processability. With the success of MHP solar cells and light-emitting diodes (LEDs), MHPs have also exhibited great potential as gain media for on-chip lasers. However, to date, stable operation of optically pumped MHP lasers and electrically driven MHP lasers — an essential requirement for MHP laser's insertion into chip-scale photonic integrated circuits — have not yet been demonstrated. The main obstacles include the instability of MHPs in the atmosphere, rudimentary MHP laser cavity patterning methods, and insufficient understanding of emission mechanisms in MHP materials and cavities. This review aims to provide a detailed overview of different strategies to improve the intrinsic properties of MHPs in the atmosphere and to establish an optimal MHP cavity patterning method. In addition, this review discusses different emission mechanisms in MHP materials and cavities and how to distinguish them. 

Traps play a key role in the performance of infrared (IR) organic photodetectors (OPDs). However, the correlation between trap states and the device performance remains unclear, and the methods to modify trap states are very limited. In this work, inverted OPD devices based on PTB7-Th and COTIC-4Cl are fabricated by employing a layer-by-layer (LbL) solution processing method. LbL solution processing enhances the crystallinity and reduces the density of trap states, thereby mitigating carrier recombination and improving photoresponsivity. Moreover, a wide-bandgap polymer, poly(N-vinylcarbazole) (PVK), is introduced to further tailor the trap distribution, shifting it from shallower to deeper energy levels. Such changes in trap distribution suppress charge carrier injection under reverse bias resulting in a lower dark current. Finally, a high specific detectivity (D*) of over 1012 Jones at 1050 nm is achieved under a bias of −0.2 V with a dark current of 6.94 × 10−9 A cm−2. These results elucidate the important relationship of trap energy distribution with the device performance and provide a versatile additive incorporation method to tailor energetic position of trap states, advancing the development of high-performance SWIR OPDs. 

Abstract Electron–phonon interactions play an essential role in charge transport and transfer processes in semiconductors. For most structures, tailoring electron–phonon interactions for specific functionality remains elusive. Here, it is shown that, in hybrid perovskites, coherent phonon modes can be used to manipulate charge transfer. In the 2D double perovskite, (AE2T)₂AgBiI₈(AE2T: 5,5“‐diylbis(amino‐ethyl)‐(2,2”‐(2)thiophene)), the valence band maximum derived from the [Ag_0.5Bi_0.5I₄]^2–framework lies in close proximity to the AE2T‐derived HOMO level, thereby forming a type‐II heterostructure. During transient absorption spectroscopy, pulsed excitation creates sustained coherent phonon modes, which periodically modulate the associated electronic levels. Thus, the energy offset at the organic–inorganic interface also oscillates periodically, providing a unique opportunity for modulation of interfacial charge transfer. Density‐functional theory corroborates the mechanism and identifies specific phonon modes as likely drivers of the coherent charge transfer. These observations are a striking example of how electron–phonon interactions can be used to manipulate fundamentally important charge and energy transfer processes in hybrid perovskites. 

The vast chemical space of emerging semiconductors, like metal halide perovskites, and their varied requirements for semiconductor applications have rendered trial-and-error environmentally unsustainable. In this work, we demonstrate RoboMapper, a materials acceleration platform (MAP), that achieves 10-fold research acceleration by formulating and palletizing semiconductors on a chip, thereby allowing high-throughput (HT) measurements to generate quantitative structure-property relationships (QSPRs) considerably more efficiently and sustainably. We leverage the RoboMapper to construct QSPR maps for the mixed ion FA 1-y Cs y Pb(I 1-x Br x ) 3 halide perovskite in terms of structure, bandgap, and photostability with respect to its composition. We identify wide-bandgap alloys suitable for perovskite-Si hybrid tandem solar cells exhibiting a pure cubic perovskite phase with favorable defect chemistry while achieving superior stability at the target bandgap of 1.7 eV. RoboMapper’s palletization strategy reduces environmental impacts of data generation in materials research by more than an order of magnitude, paving the way for sustainable data-driven materials research. 

Recent successful integration of semiconductors into spintronic THz emitters has demonstrated a new pathway of control over terahertz (THz) radiation through ultrafast demagnetization dynamics. Here, the spintronic THz emission from different ultrawide bandgap (UWBG) semiconductors interfaced with ferromagnets is studied. The authors show that the Schottky barrier in the UWBG semiconductor AlN acts as a spin filter that increases the polarization of the spin current injected from the ferromagnet. Furthermore, the authors show that the two-dimensional electron gas at the interface between Al0.25Ga0.75N and GaN enhances the magnitude of the emitted radiation due to the high spin-to-charge conversion efficiency induced by the Rashba effect that results in a hallmark asymmetry in emission amplitude. The results provide a framework for future engineering of semiconducting/ferromagnet heterostructures for ultrafast communications technologies beyond 5G.