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Many applications require monitoring of increasingly high neutron flux levels. Pre‐neutron characterization is performed of a superconducting transition edge bolometric device, sensitive to neutrons by an enriched boron carbide (10B4C) layer. Heat from the absorption of neutrons is simulated using an attenuated laser, while the detector is cooled to the critical temperature, Tc. Frequency dependent (4–25 Hz) and constant input power measurements are performed on a 10B4C‐coated and a non‐coated pixel. Results are used to fit a two lumped element thermal model. The effective specific heat is highly dependent on the input pulse duration due to the interconnected stack structure. For modulated pulses, the active volume in the thermal circuit is the full depth of the substrate in the area under the pixel. For constant power input, a large portion of the substrate is heated and the interface conductivities to the cold finger are found to be important. The detectivity is D* = 3.5 × 108 cmHzW−1${{\rm cm}} \sqrt {{\rm Hz}}\,{{\rm W}^{-1}}$, and is only slightly lower than similar detectors. Understanding the dynamics of the detector better and using neutron excitation, it is expected that optimizations can lead to an equally good detector for cold to thermal neutrons at flux levels >106 n cm−2s−1. [ABSTRACT FROM AUTHOR]

A photodetector with bias‐tuneable current is realized by adding a film of single‐walled carbon nanotubes (CNT), forming a CNT/Si3N4/Si capacitor, to a prefabricated Pt–Ti/Si3N4/Si metal–insulator–semiconductor (MIS) diode. Electrical characterization of the entire device is performed to extract the temperature‐dependent ideality factor and Schottky barrier height in the framework of the thermionic emission theory. The CNT/Si3N4/Si capacitor increases the reverse current of the parallel Pt–Ti/Si3N4/Si MIS diode by adding a Fowler–Nordheim tunneling current at high reverse voltage bias. This feature endows the photodetector with two different photocurrent levels, photoresponsivity up to 370 mA W−1 and external quantum efficiency up to 50% at 950 nm wavelength. The device also shows a different photoresponse when light is focused on the CNT/Si3N4/Si region or around the Pt–Ti/Si3N4/Si structure. The photodetector can also be used as an optoelectronic Boolean logic device, in which the applied voltage bias and the incident light are the two input signals, and the photocurrent is the output. Furthermore, light generates a photocurrent at zero voltage and a photovoltage at zero current, making the device a self‐powered photodetector. [ABSTRACT FROM AUTHOR]

Over the last few years, metal halide perovskites have established themselves as important materials in the field of optoelectronics. After their first application in photovoltaics, they have been successfully used in other optoelectronic devices, especially photodetectors, owing to their unparalleled optical and electronic properties. Notably, because of their unique optical and electronic properties and small physical dimensions, various carbon nanomaterials have emerged as alternatives for next‐generation optoelectronic devices, and they have also been combined with other materials to realize optimal optoelectronic performance. Some implementations of hybrid photodetectors combining metal halide perovskites with carbon nanomaterials have been reported. Here, it is presented a comprehensive review of the recent advancements in the application of carbon nanomaterials in metal halide perovskite photodetectors, with particular focus on the possible working mechanisms behind the significant enhancement of their performance. First, a brief introduction to the fundamentals of photodetection devices is presented, followed by a short discussion of the intrinsic characteristics of metal halide perovskites and carbon nanomaterials. Detailed descriptions of the operation mechanisms, the evolution of different device structures, and their optoelectronic performance are then given. Finally, the potential challenges and future perspectives for the development of high‐performance stable photodetectors based on these materials are outlined. [ABSTRACT FROM AUTHOR]

We report a dose-dependent phase evolution in Mo/Si bilayer system upon Ar+ ion beam irradiation and subsequent flash annealing at 800 °C for 60 s. Micro-structural characterization with Grazing Incidence X-ray Diffraction and Raman scattering reveals a dose-dependent nucleation of polymorphic phases occurring at the amorphized interface region. The ion beam mixing process has been investigated by Secondary Ion Mass Spectrometry and Rutherford Backscattering Spectrometry. While low ion doses favour nucleation of only metastable MoSi2 phase, co-existence of polymorphic phases are observed at high ion doses. The persistence of such polymorphic phases even after a high-temperature anneal for high dose implanted specimen is indicative of phase retardation. The phase retardation of h-MoSi2 to t-MoSi2 is accounted in terms of nucleation and growth process. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The Hall‐effect measurement data on n‐InP samples reported in the literature are analyzed on the basis of an impurity‐Hubbard‐band model to show the significant effects of the top Hubbard band (D− band) on the Hall coefficient and the Hall mobility. The activation energy E2 of hopping drift mobility in the top Hubbard band is deduced and is shown to obey the relation of E2∝(dND−dNDcr), where dND is the average net donor separation and dNDcr is its critical value at which the metal–insulator transition occurs. [ABSTRACT FROM AUTHOR]