Volume 2

  • No. 12 December 2019

    Touchscreen tags for the Internet of Everything

    Radio-frequency identification tags built from thin-film transistor technology can communicate with commercial capacitive touchscreens, allowing these ubiquitous screens to be used as reader interfaces. The tags can also be powered by thin-film photovoltaic cells that convert light from the touchscreens. The cover shows a photograph of the capacitive tags fabricated on a plastic substrate.

    See Papadopoulos et al.

  • No. 11 November 2019

    Transducers get thin and integrated

    Ferroelectric hafnium zirconium oxide films that are only 10 nm thick can be used to create integrated nanoelectromechanical transducers. The cover shows a scanning electron microscopy image of a nanomechanical resonator built by integrating the transducer (highlighted in pink) into an aluminium nitride (highlighted in green) on silicon membrane.

    See Ghatge et al.

  • No. 10 October 2019

    Putting a stamp on curvy electronics

    A latex balloon can be used as a stamp to pick up electronic circuits and then print them onto curved surfaces, allowing devices such as smart contact lenses to be created. The cover shows a photograph of different devices (clockwise from top: a solar cell array, a photodetector array and a serpentine metal mesh) that were printed onto silicone hemispherical shells using the approach.

    See Sim et al.

  • No. 9 September 2019

    Memristors and CMOS take AI to the edge

    Energy-efficient AI processors can be built from a computing-in-memory architecture that integrates a one-transistor–one-resistor ReRAM (memristor) cell array with control and readout circuits using a 65 nm foundry complementary metal–oxide–semiconductor (CMOS) process. The cover shows a photograph of the one-megabit computing-in-memory chip, which could be used in edge platforms such as mobile devices and the Internet of Things.

    See Chen et al. and News & Views by Jiang et al.

  • No. 8 August 2019

    Flexible amplifiers make heartfelt monitors

    A differential amplifier that is only two micrometres thick and based on organic electronics can provide electrocardiograms — a recording of the electrical activity of a person’s heart — with high signal-to-noise ratios. The cover shows a photograph of the ultraflexible circuit, which can be crumpled like a plastic wrapper and can conform to a person’s skin.

    See Sugiyama et al. and News & Views by Myny

  • No. 7 July 2019

    Memristors and CMOS integrate to multiply

    By integrating a memristor crossbar array with complementary metal–oxide–semiconductor (CMOS) control circuitry, a programmable neuromorphic computing chip can be created that is capable of efficient multiply–accumulate operations. The cover shows an optical microscopy image of the integrated chip, with the 54 × 108 crossbar array at the centre.

    See Cai et al. and News & Views by James

  • No. 6 June 2019

    A new look for body sensor networks

    Clothing made from a conductive fabric that supports surface-plasmon-like modes at radio frequencies can be used to connect wearable sensors around the body, creating a secure and energy-efficient body sensor network. The cover shows a photograph of a wirelessly powered Bluetooth module, that can transmit data to a nearby smartphone, placed on this metamaterial textile.

    See Tian et al. and News & Views by Yuce

  • No. 5 May 2019

    An ideal platform

    A device platform that uses transferred contacts made from a hexagonal boron nitride layer with embedded metal can create two-dimensional transistors with near-ideal device characteristics. The cover shows an optical microscopy image of a field-effect transistor made from bilayer tungsten diselenide built using the platform.

    See Jung et al. and News & Views by Park

  • No. 4 April 2019

    Silicon qubits find the right pulse

    Pulse engineering techniques can reduce error rates in silicon quantum dot spin qubits by a factor of three compared with state-of-the-art silicon devices. The schematic illustration on the cover highlights the errors (depicted as coloured stripes) accumulated over time for a 90° rotation of two single-spin qubits in a noisy environment, one using conventional square pulse control (far) and the other using optimized pulse engineering techniques (near).

    See Yang et al. and News & Views by Emerson

  • No. 3 March 2019

    Spins go the distance in organic semiconductors

    Long spin diffusion lengths of more than 1 μm have been measured in doped conjugated organic polymers, suggesting the materials could be of use in spintronic applications. The blueprint-themed schematic illustration on the cover highlights the lateral architecture of the spin transport device used in the experiments, which is based on spin pumping injection and inverse spin Hall detection.

    See Wang et al. and News & Views by Richter et al.

  • No. 2 February 2019

    Self-healing whatever the weather

    A conductive skin-like material, which is composed of an elastomer and an ionic liquid, can self-heal in both wet and dry conditions due to reversible ion–dipole interactions. The cover shows a photograph of an ionic circuit board, with embedded light-emitting diodes, made from the transparent material.

    See Cao et al. and News & Views by Majidi

  • No. 1 January 2019

    Microsystems compress for success

    Two-dimensional shapes made of a layer of piezoelectric polymer sandwiched between metal electrodes can be converted into sophisticated three-dimensional microsystems that have a range of applications through a compressive buckling process. The cover shows a scanning electron microscopy image of a fractal curve structure with a very low stiffness that was created using the process.

    See Han et al. and News & Views by Haghiashtiani et al.