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Extreme miniaturization of infrared spectrometers is critical for their integration into next-generation consumer electronics, wearables and ultrasmall satellites. In the infrared, there is a necessary compromise between high spectral bandwidth and high spectral resolution when miniaturizing dispersive elements, narrow band-pass filters and reconstructive spectrometers. Fourier-transform spectrometers are known for their large bandwidth and high spectral resolution in the infrared; however, they have not been fully miniaturized. Waveguide-based Fourier-transform spectrometers offer a low device footprint, but rely on an external imaging sensor such as bulky and expensive InGaAs cameras. Here we demonstrate a proof-of-concept miniaturized Fourier-transform waveguide spectrometer that incorporates a subwavelength and complementary-metal–oxide–semiconductor-compatible colloidal quantum dot photodetector as a light sensor. The resulting spectrometer exhibits a large spectral bandwidth and moderate spectral resolution of 50 cm−1 at a total active spectrometer volume below 100 μm × 100 μm × 100 μm. This ultracompact spectrometer design allows the integration of optical/analytical measurement instruments into consumer electronics and space devices.A Fourier-transform waveguide spectrometer is demonstrated by using HgTe-quantum-dot-based photoconductors with a spectral response up to a wavelength of 2 μm. The spectral resolution is 50 cm–1. The total active spectrometer volume is below 100 μm × 100 μm × 100 μm.

Infrared light detection enables diverse technologies ranging from night vision to gas analysis. Emerging technologies such as low‐cost cameras for self‐driving cars require highly sensitive, low‐cost photodetector cameras with spectral sensitivities up to wavelengths of 10 µm. For this purpose, colloidal quantum dot (QD) graphene phototransistors offer a viable alternative to traditional technologies owing to inexpensive synthesis and processing of QDs. However, the spectral range of QD/graphene phototransistors is thus far limited to 1.6 µm. Here, HgTe QD/graphene phototransistors with spectral sensitivity up to 3 µm are presented, with specific detectivities of 6 × 108 Jones at a wavelength of 2.5 µm and a temperature of 80 K. Even at kHz light modulation frequencies, specific detectivities exceed 108 Jones making them suitable for fast video imaging. The simple device architecture and QD film patterning in combination with a broad spectral sensitivity manifest an important step toward low‐cost, multi‐color infrared cameras. Colloidal quantum dot/graphene phototransistors offer a viable alternative to traditional infrared detector technologies owing to inexpensive synthesis and processing of QDs. Here, the spectral sensitivity is extended up to 3 µm with HgTe QD/graphene phototransistors presenting specific detectivities of 6 × 108 Jones, and kHz operation demonstrating potential for fast video imaging.

Near‐infrared (NIR) light detection at wavelengths λ > 1100 nm is essential in modern science and technology. Emerging organic semiconductors are promising for solution‐processed, flexible, and large‐area NIR organic photodetectors (OPDs), but only a few organic chromophores with peak absorption beyond the silicon bandgap are available. Furthermore, the external quantum efficiency (EQE) and specific detectivity (D*) of NIR OPDs are restricted by insufficient exciton dissociation and high dark/noise current. Here, the combination of strong electron‐accepting and ‐donating groups is used to synthesize a selection of novel NIR squaraine dyes with superior redshifted absorptions, peaking at 1165 nm in solution and extending to 1240 nm in a blend film. To overcome the tradeoff between long wavelength absorption and high photoresponse, NIR photons are detected utilizing a gain OPD design, where photomultiplication occurs via squaraine hole trap‐induced injection of external charges. The OPD can achieve an EQE of 220% at 1240 nm and still maintains 25% in the absorption tail at 1400 nm, thereby surpassing existing NIR OPDs in a broad wavelength range beyond 1100 nm. The measured maximum D* equals 109 Jones at 1240 nm, and the detectivity estimated from the shot noise is ≈1011 Jones, independent of the bias voltage. The synthesis of a range of squaraine dyes is reported with maximum absorption in solution above 1100 nm. Near‐infrared sensitive organic photomultiplication photodetectors are developed. Photomultiplication occurs via squaraine hole trap‐induced injection of electrons from the external circuit. Photodetectors achieve an external quantum efficiency of 220% at 1240 nm.

Aerial robots can autonomously collect temporal and spatial high‐resolution environmental data. This data can be utilized to develop mathematical ecology models to understand the impact of climate change on the habitat. In case of drone malfunction, the incorporated materials can threaten vulnerable environments. The recent introduction of transient robotics enables the development of biodegradable, environmental‐sensing drones capable of degrading in their environment. However, manufacturing methods for environmental‐sensing transient drones are rarely discussed. Herein, a manufacturing framework and material selection process featuring biopolymer‐based, high‐strength composite cryogels, and printed carbon‐based electronics for transient drones are highlighted. It is found that gelatin‐ and cellulose‐based cryogels mechanically outperform other biopolymer composites while having a homogeneous microstructure and high stiffness‐to‐weight ratio. The selected materials are used to manufacture a flying‐wing air‐frame, while the incorporated sensing skin is capable of measuring the elevons’ deflection angles as well as ambient temperature. It is demonstrated in the results how gelatin–cellulose cryogels can be used to manufacture lightweight transient drones, while printing carbon‐conductive electronics is a viable method for designing sustainable, integrated sensors. The proposed methods can be used to guide the development of lightweight and rapidly degrading robots, featuring eco‐friendly sensing capabilities. An interactive preprint version of the article can be found here: https://doi.org/10.22541/au.167506513.33779420/v1. Transient robots are biodegradable tools toward sustainable environmental monitoring in remote locations. Herein, manufacturing techniques are proposed to fabricate aerial robots from nonfossil, high‐performance, and lightweight biopolymer composite cryogels. By embodying inkjet‐printed carbon‐conductive sensors, proprioceptive and exteroceptive sensing capabilities can be added and the aerial robots data transmission and flightworthiness are demonstrated.

THz-Time domain spectroscopic imaging is demonstrated combining a robotic scanning method with continuous signal acquisition and holographic reconstruction of the object to improve the imaging resolution. We apply the method to a metallic Siemens star in order to quantify resolution and to wood samples to demonstrate the technique on a non-metallic object with an unknown structure.

As Large Language Models and Natural Language Processing (NLP) technology rapidly develop and spread into daily life, it becomes crucial to anticipate how their use could harm people. One problem that has received a lot of attention in recent years is that this technology has displayed harmful biases, from generating derogatory stereotypes to producing disparate outcomes for different social groups. Although a lot of effort has been invested in assessing and mitigating these biases, our methods of measuring the biases of NLP models have serious problems and it is often unclear what they actually measure. In this paper, we provide an interdisciplinary approach to discussing the issue of NLP model bias by adopting the lens of psychometrics — a field specialized in the measurement of concepts like bias that are not directly observable. In particular, we will explore two central notions from psychometrics, the construct validity and the reliability of measurement tools, and discuss how they can be applied in the context of measuring model bias. Our goal is to provide NLP practitioners with methodological tools for designing better bias measures, and to inspire them more generally to explore tools from psychometrics when working on bias measurement tools. This article appears in the AI & Society track.

Infrared light detection enables diverse technologies ranging from night vision to gas analysis. Emerging technologies such as low‐cost cameras for self‐driving cars require highly sensitive, low‐cost photodetector cameras with spectral sensitivities up to wavelengths of 10 µm. For this purpose, colloidal quantum dot (QD) graphene phototransistors offer a viable alternative to traditional technologies owing to inexpensive synthesis and processing of QDs. However, the spectral range of QD/graphene phototransistors is thus far limited to 1.6 µm. Here, HgTe QD/graphene phototransistors with spectral sensitivity up to 3 µm are presented, with specific detectivities of 6 × 10 8  Jones at a wavelength of 2.5 µm and a temperature of 80 K. Even at kHz light modulation frequencies, specific detectivities exceed 10 8  Jones making them suitable for fast video imaging. The simple device architecture and QD film patterning in combination with a broad spectral sensitivity manifest an important step toward low‐cost, multi‐color infrared cameras.

The rapid evolution of the neuromorphic computing stimulates the search for novel brain-inspired electronic devices. Synaptic transistors are three-terminal devices that can mimic the chemical synapses while consuming low power, whereby an insulating dielectric layer physically separates output and input signals from each other. Appropriate choice of the dielectric is crucial in achieving a wide range of operation frequencies in these devices. Here we report synaptic transistors with printed aluminum oxide dielectrics, improving the operation frequency of solution-processed synaptic transistors by almost two orders of magnitude to 50 kHz. Fabricated devices, yielding synaptic response for all audio frequencies (20 Hz to 20 kHz), are employed in an acoustic response system to show the potential for future research in neuro-acoustic signal processing with printed oxide electronics.

The use of drones and other forms of targeted killings are being increasingly criticized at the international and domestic level. Before the backdrop of the most recent news that the United Nations has launched an inquiry into the overall legality of such a method of warfare and counterterrorism and its associated loss of civilian life, this article aims to give an overview on targeted killings as a means of warfare. The article asks what constitutes targeted killing and what distinguishes it from assassinations. It reflects on the safeguards, which are necessary to ensure the legality of the targeting process. This article further introduces the reader to an updated account of the use of Unmanned Combat Aircraft Systems, or 'drones', in targeted killings, employed as a means of warfare by the USA in its 'War on Terror'. The US drone campaign in Pakistan also raises questions in respect to State Sovereignty and potential violations of this central tenet of International Law. The article will also touch upon another field of global security, so called 'Hybrid Threats', where the use of targeted killing may have an operational military benefit as part of a holistic counterstrategy. It concludes with a sobering warning that while targeted killing operations may be an effective means of achieving short-term tactical goals within the scope of a wider operational objective, the unregulated and increased use of targeting killings by the USA in the 'War on Terror' would be both immoral as well as illegal in the long run.

Since the first description of nuclear autoantigens in the late 1960s and early 1970s, researchers, including ourselves, have found it difficult to establish monoclonal antibodies (mabs) against nuclear antigens, including the La/SS-B (Sjögrens’ syndrome associated antigen B) autoantigen. To date, only a few anti-La mabs have been derived by conventional hybridoma technology; however, those anti-La mabs were not bona fide autoantibodies as they recognize either human La specific, cryptic, or post-translationally modified epitopes which are not accessible on native mouse La protein. Herein, we present a series of novel murine anti-La mabs including truly autoreactive ones. These mabs were elicited from a human La transgenic animal through adoptive transfer of T cells from non-transgenic mice immunized with human La antigen. Detailed epitope and paratope analyses experimentally confirm the hypothesis that somatic hypermutations that occur during T cell dependent maturation can lead to autoreactivity to the nuclear La/SS-B autoantigen.