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Categories: Geoscience: Volcanoes, Physics: General

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Beyond-silicon technology demands ultra-high-performance field-effect transistors (FETs). Transition metal dichalcogenides (TMDs) provide an ideal material platform, but the device performances such as contact resistance, on/off ratio, and mobility are often limited by the presence of interfacial residues caused by transfer procedures. We show an ideal residue-free transfer approach using polypropylene carbonate (PPC) with a negligible residue for monolayer MoS2. By incorporating bismuth semimetal contact with atomically clean monolayer MoS2-FET on h-BN substrate, we obtain an ultralow Ohmic contact resistance approaching the quantum limit and a record-high on/off ratio of ~1011 at 15 K. Such an ultraclean fabrication approach could be the ideal platform for high-performance electrical devices using large-area semiconducting TMDs.

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Scientists demonstrated a conceptual breakthrough by fabricating atomically precise quantum antidots using self-assembled single vacancies in a two-dimensional transition metal dichalcogenide.

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Researchers have mathematically derived the fundamental limit of heat current flowing into a quantum system comprising numerous quantum mechanical particles in relation to the particle count. Further, they established a clearer understanding of how the heat current rises with increasing particle count, shedding light on the performance constraints of potential future quantum thermal devices.

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Digital information exchange can be safer, cheaper and more environmentally friendly with the help of a new type of random number generator for encryption. The researchers behind the study believe that the new technology paves the way for a new type of quantum communication.

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What is the risk of a volcano erupting? To answer this question, scientists need information about its underlying internal structure. However, gathering this data can take several years of fieldwork, analyses and monitoring, which explains why only 30% of active volcanoes are currently well documented. A team has developed a method for rapidly obtaining valuable information. It is based on three parameters: the height of the volcano, the thickness of the layer of rock separating the volcano's reservoir from the surface, and the average chemical composition of the magma.

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Researchers have been able to substantially improve photoclick chemistry. They were able to boost the reactivity of the photoclick compound in the popular PQ-ERA reaction through strategic molecular substitution. They now report a superb photoreaction quantum yield, high reaction rates and notable oxygen tolerance.

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Researchers have developed a new approach to building quantum repeaters, devices that can link quantum computers over long distances. The new system transmits low-loss signals over optical fiber using light in the telecom band, a longstanding goal in the march toward robust quantum communication networks.

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Molecular photoswitches that can both convert and store energy could be used to make solar energy harvesting more efficient. A team of researchers has used a quantum computing method to find a particularly efficient molecular structure for this purpose. Their procedure was based on a dataset of more than 400,000 molecules, which they screened to find the optimum molecular structure for solar energy storage materials.

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The neutron-rich oxygen isotopes oxygen-27 and oxygen-28 exist as very short-lived resonances, report scientists based on the first observation of their decay into oxygen-24 and three and four neutrons, respectively. Notably, the oxygen-28 nucleus is found not to be 'doubly magic' as expected in the standard shell-model picture. This study provides valuable insights into the nuclear structure.

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Quantum physics has allowed for the creation of sensors far surpassing the precision of classical devices. Now, several new studies show that the precision of these quantum sensors can be significantly improved using entanglement produced by finite-range interactions. Researchers were able to demonstrate this enhancement using entangled ion-chains with up to 51 particles.

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Researchers have shown that dissipative Kerr solitons (DKSs) can be used to create chip-based optical frequency combs with enough output power for use in optical atomic clocks and other practical applications. The advance could lead to chip-based instruments that can make precision measurements that were previously possible only in a few specialized laboratories.

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The Mpemba effect is originally referred to the non-monotonic initial temperature dependence of the freezing start time, but it has been observed in various systems -- including colloids -- and has also become known as a mysterious relaxation phenomenon that depends on initial conditions. However, very few have previously investigated the effect in quantum systems. Now, the temperature quantum Mpemba effect can be realized over a wide range of initial conditions.

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It has long been known that graphene has excellent electronic properties. However, it was unclear until now how stable these properties are. Are they destroyed by disturbances and additional effects, which are unavoidable in practice, or do they remain intact? Scientists have now succeeded in developing a comprehensive computer model of realistic graphene structures. It turned out that the desired effects are very stable. Even graphene pieces that are not quite perfect can be used well for technological applications.

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Physicists have developed a technique to precisely control the alignment of supermoiré lattices by using a set of golden rules, paving the way for the advancement of next generation moiré quantum matter.

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Researchers have implemented a quantum-based method to observe a quantum effect in the way light-absorbing molecules interact with incoming photons. Known as a conical intersection, the effect puts limitations on the paths molecules can take to change between different configurations. The observation method makes use of a quantum simulator, developed from research in quantum computing, and offers an example of how advances in quantum computing are being used to investigate fundamental science.

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Many songbirds use the earth's magnetic field as a guide during their migrations, but radiowaves interfere with this ability. A new study has found an upper bound for the frequency that disrupts the magnetic compass.

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Scientists have developed a new method for detecting mid-infrared (MIR) light at room temperature using quantum systems.

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Using a trapped-ion quantum computer, the research team witnessed the interference pattern of a single atom caused by a 'conical intersection'. Conical intersections are known throughout chemistry and are vital to rapid photo-chemical processes such as light harvesting in human vision or photosynthesis.

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A new approach to quantum light emitters generates a stream of circularly polarized single photons, or particles of light, that may be useful for a range of quantum information and communication applications. A team stacked two different, atomically thin materials to realize this chiral quantum light source.

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The measurement values determined in sufficiently precise measurements of physical systems will vary based on the relation between the past and the future of a system determined by its interactions with the meter. This finding may explain why quantum experiments often produce paradoxical results that can contradict our common-sense idea of physical reality.