Articles tagged with "optoelectronics"
Self-etching process opens new pathways for 2D perovskite electronics
A collaborative research team from China and the US has developed a novel semiconductor fabrication method called self-etching, which addresses the limitations of conventional lithography in working with delicate two-dimensional (2D) lead halide perovskite materials. Traditional lithography techniques, which rely on vertical laser etching, often cause damage due to sideways light scattering, especially problematic for soft, chemically unstable materials like 2D perovskites. The new self-etching approach leverages the internal stress within growing perovskite crystals to form controlled lateral microstructures from within, enabling precise nanoscale patterning without the damage caused by conventional photolithography or harsh chemical solvents. This breakthrough offers a new material platform and design pathway for high-performance light-emitting and integrated electronic devices, overcoming the machining challenges that have limited the use of 2D perovskites in advanced semiconductor applications. The method allows the creation of pixel-like units with tunable color and brightness, resulting in single crystal waf
materialssemiconductor-manufacturing2D-perovskitesself-etching-processnanofabricationoptoelectronicschip-fabricationScientists make dead nanoparticles emit light with tiny antennas
Researchers at the University of Cambridge’s Cavendish Laboratory have overcome a major challenge in optoelectronics by developing a method to electrically power lanthanide-doped nanoparticles (LnNPs), which were previously considered unusable in electronic devices due to their insulating nature. The team created an organic-inorganic hybrid material by attaching an organic dye, 9-anthracenecarboxylic acid (9-ACA), to the surface of the LnNPs. This dye acts as an “antenna” that directly receives electrical charges, bypassing the insulating nanoparticles. The energy captured by the 9-ACA molecules is transferred with over 98% efficiency to the lanthanide ions, resulting in bright light emission and enabling the creation of a new class of LEDs called LnLEDs. These LnLEDs operate at low voltages (~5 volts) and emit light with exceptionally narrow spectral width in the second near-infrared (NIR-II) window, which can penetrate biological
materialsnanoparticlesoptoelectronicslight-emitting-diodeslanthanide-doped-nanoparticlesorganic-inorganic-hybridnear-infrared-LEDsWorld’s smallest neural implant tracks brain signals through light
Cornell researchers have developed the world’s smallest neural implant, called the microscale optoelectronic tetherless electrode (MOTE), which is about the size of a grain of salt (approximately 300 microns long and 70 microns wide). This implant is capable of wirelessly recording brain activity in living animals for over a year by using harmless red and infrared laser beams to power the device and transmit data through tiny pulses of infrared light. The implant’s semiconductor diode, made from aluminum gallium arsenide, captures light energy to power the circuit and sends encoded brain signals optically, employing pulse position modulation to minimize power consumption while maintaining effective data communication. The MOTE was tested in mice by implanting it in the barrel cortex, where it successfully recorded neuron spikes and synaptic activity continuously for a year without causing adverse effects or immune responses. Its extremely small size reduces brain tissue irritation and avoids the complications associated with traditional electrodes and optical fibers, which often provoke immune reactions due to tissue movement
IoTneural-implantoptoelectronicssemiconductor-materialswireless-brain-monitoringbio-integrated-sensinglow-power-communicationLight-vibration coupling opens new path for future electronics
Researchers at Rice University have achieved a breakthrough by creating hybrid phonon-polaritons in thin films of lead halide perovskite, merging atomic vibrations (phonons) with light waves to form new quantum states of matter. Using nanoscale slots in a thin gold layer to trap light at terahertz frequencies matching the phonon vibrations, the team demonstrated ultrastrong coupling between two phonon modes and light at room temperature—an achievement not previously realized in perovskite films. This coupling reached about 30% of the phonon frequency, producing three distinct hybrid states without requiring extreme conditions or high-power lasers. This advancement enables precise tuning and control of energy flow in optoelectronic materials such as solar cells and LEDs, potentially improving their efficiency by reducing energy losses. The approach relies on careful nanoscale engineering rather than bulky crystals or intense laser pulses, making it compatible with practical device fabrication. Supported by numerical simulations and quantum modeling, the study opens new possibilities for manipulating quantum
energymaterials-scienceperovskiteoptoelectronicsphonon-polaritonsnanofabricationlight-matter-interactionUS engineers build transistor-like switch for quantum excitons
University of Michigan engineers have developed the first transistor-like switch that can control the flow of excitons—quantum quasiparticles that carry energy without charge—at room temperature. Excitons form when light excites electrons in semiconductors, creating electron-hole pairs that move together as neutral energy packets. Unlike electrons, excitons do not generate heat through energy loss, making them promising candidates for more efficient computing technologies. The team overcame a major challenge by designing a nanostructured ridge that guides excitons along a controlled path and using electrodes as gates to switch exciton flow on and off, achieving an on-off switching ratio above 19 decibels. This breakthrough opens the door to excitonic circuits that could significantly reduce energy consumption and heat generation in computing systems, addressing current limitations faced by electronics in AI and other demanding applications. The researchers also demonstrated an optoexcitonic switch using light to propel excitons rapidly along the ridge, suggesting potential for faster and cooler data transfer in devices
quantum-excitonsexcitonicsnano-switchenergy-efficient-computingsemiconductor-technologyoptoelectronicssolar-cellsLab-grown brain cells steer robot dog, advancing Alzheimer's study
US scientists at the University of California San Diego have developed a novel technique called Graphene-Mediated Optical Stimulation (GraMOS) that uses graphene’s optoelectronic properties to stimulate and accelerate the maturation of lab-grown human brain organoids. Unlike traditional methods that rely on genetic modification or direct electrical currents, GraMOS is biocompatible and noninvasive, converting light into gentle electrical signals that encourage neurons to connect and mature faster. This advancement addresses the major limitation of slow brain organoid development, enhancing their utility for studying neurological diseases such as Alzheimer’s and enabling faster drug testing. In a groundbreaking demonstration, the researchers connected graphene-interfaced brain organoids to a robotic dog, allowing the organoids to process sensory input and generate neural responses that enabled the robot to avoid obstacles within 50 milliseconds. This neuro-biohybrid system exemplifies the potential for living brain cells to interface with machines, opening possibilities for applications in prosthetics, adaptive robotics, and biological computing. The
robotgraphenebrain-organoidsbrain-machine-interfaceoptoelectronicsneurological-disease-researchAlzheimer's-studyWorld's most powerful X-ray laser spots atomic shifts in solar cells
Scientists at the European XFEL research facility have, for the first time, directly observed atomic-scale deformations inside solar cell materials using the world’s most powerful X-ray laser. Led by Johan Bielecki, PhD, the team captured how electron-hole pairs—created when light excites electrons in a solar cell—cause subtle distortions in the atomic lattice of the material. These tiny deformations, previously undetectable, were visualized using femtosecond-scale X-ray pulses, revealing ultrafast interactions between electron-hole pairs and the crystal lattice. The study focused on quantum dots made of cesium, lead, and bromine (CsPbBr3), where these distortions form a state known as an exciton-polaron. The findings are significant because even minimal lattice deformations critically influence the optical and electronic properties of materials used in solar cells, displays, sensors, and potentially quantum computing components. Zhou Shen, PhD, the study’s lead author, emphasized that understanding these
energysolar-cellsmaterials-scienceX-ray-laserquantum-dotsoptoelectronicsatomic-lattice-deformationBreakthrough camouflage for soldiers copies plants, dodges enemy lasers
Chinese scientists from the Micro-Nano Optoelectronics and Intelligent Sensing Research Group at the National University of Defense Technology have developed an advanced multispectral camouflage device inspired by the infrared radiation characteristics of Rosaceae plants. Utilizing the phase change material In3SbTe2 (IST), the device achieves multifunctional capabilities including infrared camouflage, thermal management, laser stealth, and visible light camouflage. The design employs particle swarm optimization combined with finite difference time domain methods to optimize performance, enabling it to mimic plant emissivity in key atmospheric infrared windows (3–5 µm and 8–14 µm) and achieve ultra-low emissivity for stealth. The device demonstrates impressive results in both its amorphous and crystalline states, with emissivities closely matching those of natural leaves, thus effectively blending into infrared imaging. It also achieves high laser absorption rates at wavelengths of 1.064 µm, 1.55 µm, and 10.6 µm, enabling laser stealth capabilities. Thermal management
materialsphase-change-materialsinfrared-camouflagethermal-managementlaser-stealthoptoelectronicsmilitary-technologyEuropean quantum scientists flip excitons like light switches
Researchers from the University of Innsbruck, in collaboration with universities in Dortmund, Bayreuth, and Linz, have developed a novel technique to control dark excitons in semiconductor quantum dots using chirped laser pulses and magnetic fields. Excitons are quasiparticles formed when an electron is excited to a higher energy state, leaving behind a positively charged hole; the electron and hole pair orbit each other due to Coulomb attraction. Excitons are categorized as bright or dark based on their interaction with light: bright excitons can absorb or emit photons, while dark excitons, likely due to differing spin configurations, do not interact optically and thus have longer lifetimes, making them promising for energy storage and quantum information applications. The team demonstrated the ability to switch bright excitons into dark excitons and vice versa, effectively using dark excitons as a quantum memory by storing quantum states in a non-radiative form and reactivating them later with laser pulses. This controlled manipulation opens new avenues
materialsquantum-dotsexcitonssemiconductorenergy-storageoptoelectronicsquantum-entanglementShapeshifting perovskites can help make solar devices, LEDs more efficient
Researchers from the University of Utah have demonstrated that wafer-thin Ruddlesden-Popper (RP) metal-halide hybrid perovskites, a class of two-dimensional layered materials composed of alternating inorganic and organic sheets, exhibit temperature-dependent phase transitions that significantly influence their optical properties. These phase transitions, akin to changes between different solid states as seen in water, alter the structure of the inorganic layers through the melting and disordering of organic chains, thereby modulating the material’s light emission wavelength and intensity. This dynamic tunability enables the emission wavelength to be adjusted across a broad spectrum from ultraviolet to near-infrared, offering valuable control for optoelectronic applications such as LEDs and thermal energy storage. The study highlights that these perovskites’ optical properties shift continuously with temperature due to subtle structural distortions, revealing a strong interplay between organic and inorganic components that can be manipulated at the molecular level. Importantly, perovskites present a promising alternative to traditional silicon in solar cell
perovskitesmaterials-sciencerenewable-energysolar-technologyLEDsthermal-energy-storageoptoelectronicsEye-opening device: Self-powered AI synapse mimics human vision, achieves 82% accuracy
energyAIoptoelectronicssolar-cellsvisual-recognitionlow-power-systemsautonomous-vehicles