Articles tagged with "2D-materials"
Hexatic phase melting observed in real-time in ultra-thin materials
Researchers at the University of Vienna have, for the first time, directly observed the melting process of ultra-thin, two-dimensional (2D) materials at the atomic level. Using a single atomic-thick layer of silver iodide (AgI) sandwiched between graphene sheets and heated inside a scanning transmission electron microscope (STEM), they captured real-time video of melting. This setup, combined with AI neural networks to track individual atoms across thousands of frames, allowed unprecedented insight into the phase transitions of 2D materials, which differ fundamentally from bulk materials due to atomic movement restricted to a flat plane. Their observations confirmed the existence of the hexatic phase—a state theorized since the 1970s but never directly seen in naturally bonded materials—where atomic distances become irregular like a liquid, yet angular order remains as in a solid. Importantly, while the transition from solid to hexatic phase occurred gradually as expected, the subsequent transition from hexatic to liquid was abrupt rather than continuous,
materials2D-materialsphase-transitionshexatic-phasemelting-processatomic-level-observationgrapheneNew ultrathin metasurface boosts photon generation for next-gen quantum chips
Columbia Engineering researchers have developed an ultrathin metasurface device that significantly enhances nonlinear optical effects at the nanoscale, advancing the miniaturization of quantum hardware. Building on prior work where a 3.4-micrometer-thick crystalline device generated entangled photon pairs, the team has now reduced the thickness to just 160 nanometers by introducing metasurfaces—artificial nanoscale patterns etched into ultrathin crystals. This approach boosts second harmonic generation by nearly 150 times compared to unpatterned samples, enabling more efficient photon generation at telecom wavelengths, which is crucial for future quantum devices. The research focuses on transition metal dichalcogenides, specifically molybdenum disulfide flakes, which are atomically thin but previously limited in photon generation efficiency. By etching repeating nanoscale lines into these flakes, the team achieved strong nonlinear optical effects beyond traditional methods, while simplifying fabrication using standard cleanroom tools. This breakthrough paves the way for compact, integrable quantum phot
materialsquantum-materialsmetasurfacesphoton-generationnonlinear-optics2D-materialsquantum-technologyLight reveals atoms dancing for the first time in 2D materials
Researchers from Cornell and Stanford Universities have, for the first time, directly observed atoms in two-dimensional (2D) moiré materials dynamically twisting and untwisting in response to light. These ultrathin materials, composed of stacked atomic layers, exhibit unusual properties such as superconductivity and magnetism when slightly twisted. Using ultrafast electron diffraction combined with Cornell’s custom-built Electron Microscope Pixel Array Detector (EMPAD), the team captured this rapid atomic motion occurring within a trillionth of a second, revealing that these materials are not static but rhythmically flex and twist under laser pulses. This breakthrough challenges the previous assumption that moiré materials remain fixed once stacked at a certain angle. Instead, the study shows that light can dynamically enhance and control the twisting motion in real time, opening new possibilities for manipulating quantum behaviors in 2D materials. The collaboration leveraged Stanford’s expertise in engineered materials and Cornell’s advanced imaging technology, enabling the first direct visualization of these ultrafast atomic shifts.
materials2D-materialsmoiré-materialsultrafast-electron-diffractionatomic-motionquantum-materialslaser-pulsesScientists make dark excitons 300,000x brighter for quantum tech
Scientists from City University of New York (CUNY) and the University of Texas at Austin have made a significant breakthrough by amplifying the light emission of dark excitons—normally invisible quantum light-matter states found in atomically thin semiconductors—by nearly 300,000 times. Using a nanoscale optical cavity composed of gold nanotubes and a single atomic layer of tungsten diselenide (WSe₂), the team made these elusive states not only visible but also controllable at the nanoscale. This advance holds promise for developing faster, smaller, and more energy-efficient quantum computing and photonic technologies due to dark excitons’ long lifetimes and low environmental interactions. Further, the researchers demonstrated precise tuning of dark excitons using electric and magnetic fields, enabling on-demand control of their emission without altering the semiconductor’s natural properties. This approach preserves the material’s integrity while achieving record-breaking light-matter coupling. The study also resolved a longstanding debate in nanophotonics by showing that
quantum-computingphotonicsdark-excitons2D-materialsenergy-efficient-technologynanoscale-controlquantum-information2D flash-silicon chip achieves record speed, 94% memory yield
Researchers at Fudan University have developed the world’s first full-featured 2D flash memory chip integrated with traditional silicon CMOS technology, achieving a record operation speed and a 94.3% memory cell yield. This hybrid chip supports eight-bit instruction operations and 32-bit high-speed parallel random access, surpassing existing flash memory speeds. The innovation represents a significant breakthrough in combining ultrathin 2D semiconductor materials—just a few atoms thick—with mature silicon platforms, addressing key limitations in speed and power consumption that have hindered AI and data-intensive computing systems. The team overcame major challenges in integrating fragile 2D materials onto the uneven surfaces of conventional silicon wafers by employing flexible 2D materials and a modular, atomic-scale bonding approach. This method enables stable, high-density interconnections between the two technologies, facilitating efficient communication and paving the way for industrial-scale production. The chip has completed its tape-out phase, and plans are underway to establish a pilot production line to scale manufacturing.
materialssemiconductorflash-memory2D-materialssilicon-chipCMOS-technologydata-storageUS scientists' light-emitting material could revolutionize photonics
Researchers at UCLA’s California NanoSystems Institute have developed a novel light-emitting material by combining molybdenum disulfide (MoS₂), a two-dimensional semiconductor, with Nafion, a flexible polymer commonly used in fuel cells. This hybrid material overcomes the traditional limitations of MoS₂, which is typically fragile and emits weak light, by leveraging Nafion’s flexibility and chemical stability to reinforce the semiconductor and heal surface defects that usually reduce light output. The resulting membranes are stretchable, durable, and produce significantly brighter and more stable light emission than MoS₂ alone. This breakthrough holds significant promise for photonics, the field of technology that uses light (photons) instead of electricity (electrons) for computing and communication. The new material’s durability, flexibility, and efficiency could enable the development of stretchable displays, flexible lasers, and chip-integrated light sources. In the longer term, it may revolutionize photonic computing by enabling faster, more energy-efficient light-based circuits
materialsphotonicsmolybdenum-disulfide2D-materialsNafionlight-emitting-materialsflexible-electronicsNew 2D magnetic transistor delivers 10x stronger current switching
MIT engineers have developed a novel magnetic transistor using a two-dimensional magnetic semiconductor, chromium sulfur bromide, which enables current switching that is ten times stronger than existing magnetic transistor designs. This device operates with significantly lower energy compared to traditional silicon transistors, overcoming silicon’s voltage limitations that hinder further efficiency improvements. The magnetic semiconductor’s stable structure allows precise switching between two magnetic states, altering its electronic behavior and enabling low-energy operation. The team’s innovative fabrication method, which avoids solvents or glue by directly transferring the thin magnetic film onto a silicon substrate with tape, results in a clean interface that enhances device performance. Beyond stronger and more energy-efficient switching, the new transistor uniquely integrates logic and memory functions, allowing it to store information directly rather than relying on separate magnetic memory cells. This built-in memory capability, combined with faster and more reliable readouts due to the stronger signal, represents a significant advancement for spintronic devices. The researchers demonstrated control of the magnetic state both via external magnetic fields and electrical currents,
materialsspintronicsmagnetic-transistor2D-materialssemiconductor-physicslow-energy-electronicsmemory-devicesUltra-thin quantum sensors survive 30,000 times the pressure of air
Physicists at Washington University in St. Louis have developed ultra-thin quantum sensors made from crystallized boron nitride that can measure stress and magnetism under pressures exceeding 30,000 times atmospheric pressure. These sensors leverage vacancies created by neutron radiation beams that knock boron atoms out of the boron nitride sheets, trapping electrons whose quantum spin states change in response to local magnetic fields, stress, or temperature. Unlike previous diamond-based quantum sensors, these two-dimensional boron nitride sensors are less than 100 nanometers thick, allowing them to be placed extremely close—within a nanometer—to the material under study, enhancing measurement precision under extreme conditions. To apply such high pressures, the team uses diamond anvils—tiny, durable flat surfaces about 400 micrometers wide—that compress the sample material. Initial tests demonstrated the sensors’ ability to detect subtle magnetic changes in two-dimensional magnets. Future plans include studying materials from high-pressure environments like Earth’s core to better understand geological phenomena
quantum-sensorsboron-nitridehigh-pressure-measurementmaterials-science2D-materialsmagnetism-detectionquantum-technologyNine-metal MXene obliterates limits of 2D nanomaterial design
Scientists at Purdue University have achieved a breakthrough in two-dimensional (2D) nanomaterials by synthesizing MXenes—ultrathin sheets just a nanometer thick—that incorporate up to nine different transition metals. This represents a significant advance beyond previous MXene designs, which typically involved fewer metals. By creating nearly 40 layered materials with varying metal combinations, the researchers explored how entropy (the tendency toward atomic disorder) competes with enthalpy (the drive for ordered atomic arrangements) in these complex structures. They found that while MXenes with fewer metals tend to form ordered layers, those with higher metal diversity exhibit “high-entropy” phases characterized by atomic disorder, a transition that is crucial for designing materials stable under extreme conditions. The team first synthesized layered “parent” MAX phases before converting them into MXenes to study their surface and electronic properties, linking atomic order-disorder transitions to functional behavior. This insight expands the family of 2D materials and their potential applications in demanding environments such
materialsnanomaterialsMXene2D-materialshigh-entropy-materialsadvanced-materialsenergy-storage-materialsWrinkled 2D sheets may unlock faster, more efficient devices
Researchers at Rice University have discovered that tiny wrinkles in two-dimensional (2D) materials, such as molybdenum ditelluride, can precisely control electron spin, a quantum property that could revolutionize computing. Unlike traditional devices that rely on electron charge, spintronics uses electron spin states ("up" or "down") to process information, potentially enabling faster, smaller, and more energy-efficient devices. A major challenge in spintronics has been the rapid decay of spin information due to electron scattering, but the Rice team found that bending 2D materials creates a unique spin texture called a persistent spin helix (PSH), which preserves spin states even amid collisions. This effect arises from the flexoelectric polarization generated by uneven strain when the 2D sheet is bent—stretching on one side and compressing on the other—creating internal electric fields that split spin-up and spin-down electrons into distinct bands. The curvature-induced interaction is strongest in highly curved regions like wrinkles or
materials2D-materialsspintronicsenergy-efficient-deviceselectron-spinquantum-computingflexoelectric-polarizationNew quantum phonon interference sets stage for next-gen sensors
Researchers at Rice University have demonstrated a groundbreaking advancement in phonon interference, achieving interference effects two orders of magnitude stronger than previously observed. By intercalating a few layers of silver atoms between graphene and a silicon carbide substrate—a process called confinement heteroepitaxy—they created a unique two-dimensional metal interface that enhances vibrational mode interactions in silicon carbide. This strong phonon interference, characterized by Fano resonance patterns detected via Raman spectroscopy, reveals highly sensitive vibrational signals that can distinguish even single dye molecules on the surface, enabling label-free single-molecule detection with a simple, scalable setup. This discovery marks a significant step in harnessing phonons—quantum units of vibration that carry heat and sound—as effective carriers of quantum information, comparable to electrons and photons. Unlike bulk metals, the atomically thin 2D metal layer produces unique quantum interference pathways purely from phonon interactions, without electronic contributions. The findings open new avenues for phonon-based quantum sensing, molecular detection, energy harvesting, and
quantum-sensingphonon-interference2D-materialsgraphenesilicon-carbidemolecular-detectionenergy-technologyRecord-breaking single-photon detector ends need for cryogenics
Researchers at ICFO have developed a groundbreaking single-photon detector capable of sensing mid-infrared photons at significantly higher temperatures—around 25 Kelvin—compared to conventional detectors that require cryogenic cooling below 1 Kelvin. This advance eliminates the need for bulky, energy-intensive cryogenic systems, making the technology more practical for integration into photonic circuits. The detector is constructed from stacked two-dimensional materials, specifically bilayer graphene sandwiched between hexagonal boron nitride layers, precisely aligned to create a moiré pattern that induces a bistability effect. This bistability allows the device to switch between two stable states when triggered by a single photon, enabling detection without ultra-low temperatures. The novel detection mechanism differs fundamentally from traditional superconducting and semiconductor detectors by operating near an electrical tipping point, where a single photon acts as a trigger to switch the device’s state. This approach enhances sensitivity to long-wavelength photons and has potential applications in astronomy, quantum communication, and medical imaging by improving the
materialsgraphenephoton-detectorquantum-communication2D-materialsmid-infrared-detectioncryogenics2D InSe wafer outperforms silicon in mobility, switching, leakage
Chinese scientists have achieved a major breakthrough by fabricating the world’s first wafer-scale, two-dimensional indium selenide (InSe) semiconductor chip, which outperforms silicon in key performance metrics. Using a novel “solid–liquid–solid” growth method, the team led by Professor Liu Kaihui at Peking University produced a 2-inch InSe wafer with exceptional crystal quality, phase purity, and thickness uniformity. The resulting InSe-based transistors demonstrated electron mobility up to 287 cm²/V·s, ultra-low subthreshold swings, minimal leakage at sub-10nm gate lengths, high on/off ratios, and energy-delay products surpassing the 2037 International Roadmap for Devices and Systems (IRDS) benchmarks. This advancement overcomes longstanding challenges in synthesizing large-area InSe due to vapor pressure differences and phase instability, by maintaining a perfect atomic ratio of indium and selenium during growth. The process is compatible with existing CMOS technology, facilitating potential real
materialssemiconductorindium-selenide2D-materialswafer-scale-growthtransistor-technologynext-generation-chipsScientists capture atomic motion on camera for the first time
Scientists have, for the first time, directly filmed atomic motion by capturing thermal vibrations of atoms in real-time using an advanced electron microscopy technique called electron ptychography. Led by Yichao Zhang from the University of Maryland, the team achieved a resolution finer than 15 picometers, allowing them to visualize moiré phasons—coordinated, heat-driven vibrations that occur in twisted two-dimensional (2D) materials. These subtle atomic motions, previously only theorized, play a crucial role in determining thermal conductivity and superconductivity in ultrathin quantum materials. This breakthrough provides unprecedented insight into how heat propagates through 2D materials and confirms long-standing hypotheses about atomic-scale dynamics. By revealing these vibrations, the research opens new avenues for engineering quantum materials with tailored thermal, electronic, and optical properties. Zhang’s team plans to further explore how defects and interfaces affect thermal vibrations, which could lead to advances in quantum computing and energy-efficient electronics. Published in Science on July 24,
materials-science2D-materialselectron-microscopyatomic-motionquantum-materialsthermal-vibrationselectron-ptychographyNew clay membrane tech can extract lithium straight from water
Researchers at the U.S. Department of Energy’s Argonne National Laboratory and the University of Chicago have developed a novel, low-cost membrane technology capable of efficiently extracting lithium directly from saltwater. This membrane is made from vermiculite, a naturally abundant and inexpensive clay, which is processed into ultrathin two-dimensional sheets. To stabilize these sheets in water, the team introduced microscopic aluminum oxide pillars that maintain the membrane’s structure and enable selective ion filtration based on size and charge. By doping the membrane with sodium ions, it gains a positive surface charge that repels magnesium ions more strongly than lithium ions, allowing for effective separation of lithium from chemically similar elements. This breakthrough offers a scalable alternative to traditional lithium mining, which is costly, slow, and geographically concentrated, by tapping into the vast lithium reserves dissolved in seawater, underground brines, and wastewater. The membrane’s ability to selectively filter lithium with high precision could reduce dependence on foreign lithium suppliers and unlock new domestic sources. Beyond lithium, the
materialsenergylithium-extractionmembrane-technology2D-materialssustainable-miningwater-filtrationWorld's first 2D material built computer completely ditches silicon
Researchers at Penn State have developed the world’s first computer built entirely from two-dimensional (2D) materials, completely eliminating the use of silicon. This innovative computer uses complementary metal-oxide-semiconductor (CMOS) technology based on two different 2D materials: molybdenum disulfide for n-type transistors and tungsten diselenide for p-type transistors. Unlike silicon, which faces performance degradation as devices shrink, these 2D materials maintain exceptional electronic properties even at atomic thickness, offering a promising path for faster, thinner, and more efficient electronics. The team employed metal-organic chemical vapor deposition (MOCVD) to grow large sheets of these 2D materials and fabricated over 1,000 transistors of each type. By fine-tuning fabrication and post-processing steps, they adjusted transistor threshold voltages to build fully functional CMOS logic circuits. The resulting 2D CMOS computer operates at low supply voltages with minimal power consumption and can perform simple logic operations at
2D-materialssemiconductor-technologyCMOS-computermolybdenum-disulfidetungsten-diselenidetransistor-fabricationsilicon-alternativeNew 2D material could be used in electrochemical energy storage
materialsenergyelectrochemical2D-materialsboroncopper-boridenanomaterials