Review Articles

This Review summarizes the use of topological modes to enable compact laser architectures, alongside emerging research directions involving non-Hermitian band topology, non-linear gain dynamics and quasiperiodic ordering.

This Review surveys wireless energy conversion, a paradigm that transforms wirelessly transmitted power directly into chemical, thermal, optical or mechanical energy without intermediate storage. It covers transmission mechanisms, conversion pathways from charging to motoring, and engineering trade-offs, before identifying routes towards standardized, secure and scalable deployment.

Long-haul large-capacity 400G optical transmission over 1,500 km is possible through advanced fibre-optic systems. This Review provides a holistic view of the signal modulation, spectrum plans, optical components and optical-layer infrastructure necessary to achieve those networks.

Metalenses face both remarkable opportunities and challenges as they evolve from laboratory prototypes to practical devices. This Review highlights how advances in advanced materials, scalable manufacturing and academic–industrial synergy can transform these challenges into opportunities for the widespread implementation of metalens technologies.

This Review examines how artificial intelligence (AI) systems optimize energy and information networks independently, then coordinate renewable energy supply with traffic demand across both. This Review also assesses the carbon emissions of AI systems from their training, deployment and use, and hardware life cycle, outlining strategies to ensure the environmental benefits of AI systems outweigh their costs.

Silicon carbide power devices offer advantages over silicon, but realizing these advantages requires tailored packaging and integration strategies. This Review examines packaging materials, packaging technologies and electro-thermal co-design strategies that address the challenges of high-speed switching, concentrated heat flux and high-temperature and high-voltage operation.

Emerging bioelectronic technologies enable real-time monitoring and precise modulation of plant physiology and environmental conditions. These technologies have the potential to accelerate basic plant science research and transform sustainable agriculture.

This Review provides a holistic view of sustainable gas, liquid and solid insulating materials, focusing on substitution, benign degradation, recycling, reuse and resource conversion to support net zero power systems.

Interconnect architectures are vital frameworks that allow disparate components, such as cores and memory, to communicate. This Review provides an overview of the development of key interconnect components, such as metals, diffusion barriers and intermetal dielectrics, and how they can offer more efficient and sustainable performance.

Active-matrix digital microfluidics (AM-DMF) presents a highly scalable and programmable platform for handling microscale liquid samples. Wang et al. describe advances in AM-DMF chip design, circuit optimization and functional integration and discuss its considerable commercial potential for automated high-throughput biomedical sample manipulation.

Information security remains a vital concern for communications technology, and quantum key distribution may offer the highest security theoretically possible. This Review discusses the performance limitations, high costs and practical security concerns for quantum key distribution to scale to a global level.

Cyber–physical–human systems (CPHSs) integrate layers of physical components, computation and communication, and humans — in smart buildings, for example. This Review addresses the modelling and control of CPHSs, particularly of the human layer using game theory and opinion dynamics.

Complementary metal–oxide–semiconductor-integrated silicon photonics offers a scalable path to high-bandwidth, low-energy optical interconnects for data centres and artificial intelligence/high-performance computing. This Review surveys device maturity, multimaterial and 3D integration, electronics co-design and packaging trends and maps a path towards comb-enabled dense wavelength-division multiplexing, petabit bandwidth and sub-picojoule per bit efficiency.

Intrinsically stretchable transistors with high mobility, robustness, low-voltage operation and scalable fabrication are key for integrated circuits to advance skin-like soft electronics and to enable stable, conformal interfaces for bioelectronics, wearable technology and adaptive human–machine interfaces.

This Review discusses the design and functionality of neuromorphic olfactory perception chips, focusing on key technologies, including sensing materials, device structures and signal processing algorithms. The authors also highlight the practical applications and future prospects of these chips in various fields.

Ferroelectric switching behaviour can more closely emulate the temporal dynamics of biological neurons and synapses for neuromorphic computing. This Review clarifies the mechanism of two-terminal and three-terminal ferroelectric devices and highlights their potential for efficient in-memory and in-sensor applications.

Skin-conformal electronics enable intuitive, real-time gesture recognition through seamless integration of conformal sensing and intelligent processing. Reliable and precise human–machine interactions gain thus transformative potential in health care, robotics, immersive applications and other dynamic environments.

Extended reality (XR) promises to blend real and virtual objects and people in the metaverse. This Review overviews an XR workflow and eight key XR technologies for achieving immersive experiences in both professional settings and everyday life.

This Review provides an overview of non-biomimetic, biomimetic and neuromorphic approaches to bio-interactive prosthetics. Kim et al. highlight the advantages and challenges of artificial nerve systems for reducing computational complexity, improving biocompatibility and restoring natural sensory and motor functions in patients with neurological deficits.

The shrinking dimensions, the increased structural complexity and the 3D stacking of silicon-based semiconductor devices are intensifying challenges in thermal dissipation. This Review explores thermal management materials, integration challenges and characterization methods, and proposes a road map for efficient heat dissipation solutions in 3D integration.