Quantum dots tagged posts

A New Arrangement: Using Quantum Dots to Quench the Smallest Ferrimagnetism

Coding the T-shaped quantum-dot model
Model of the Kondo effect on minimal ferrimagnetism and finds suppression of conductivity.

Model of Lieb’s ‘minimal’ ferrimagnetism with Kondo effect using a ‘T’ of quantum dots. Dr. Nishikawa at Osaka Metropolitan University focused on the Kondo effect on minimal ferrimagnetism and attempted to elucidate it theoretically. As a result, they found that the Kondo effect occurred via multiple “quantum entangled states” depending on temperature and other factors. They also found that the Kondo effect suppressed electrical conductivity through minimal ferrimagnetism, when usually it is amplified in many other cases.

Most people are not aware of magnetic forces in their everyday lives, but continuously rely on them in electric motors, hard drives, and electric sensors...

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Mini Electricity Generator made from Quantum Dots

Mickael L. Perrin in his lab at Empa. Here he will set on to create a quantum heat engine that operates at room temperature using graphene nanoribbons. Image: Empa

Machines and electronic devices often generate waste heat that is difficult to utilize. If electricity could be generated from this waste heat, it would offer a means for a clean and sustainable power production: Such a technology would be ideally suited for low-power electronics applications such as wearables or low-cost Internet-of-Things devices. This includes, for example, wearable (medical) devices and sensors, with a wide range of applications in the healthcare and sports industry, in smart buildings and mobility applications.

Thermoelectric generators, machines that generate electricity by exploiting temperature di...

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How Quantum Dots can ‘Talk’ to Each Other

Atomistic Simulations of Laser-Controlled Exciton Transfer and Stabilization in Symmetric Double Quantum Dots
Pascal Krause*
, Jean Christophe Tremblay
, and Annika Bande

A group has worked out theoretically how the communication between two quantum dots can be influenced with light. The team shows ways to control the transfer of information or energy from one quantum dot to another. To this end, the researchers calculated the electronic structure of two nanocrystals, which act as quantum dots. With the results, the movement of electrons in quantum dots can be simulated in real time.

So-called quantum dots are a new class of materials with many applications. Quantum dots are realized by tiny semiconductor crystals with dimensions in the nanometre range...

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Cheap, Nontoxic Carbon Nanodots poised to be Quantum Dots of the Future

Tiny fluorescent semiconductor dots, called quantum dots, are useful in a variety of health and electronic technologies but are made of toxic, expensive metals. Nontoxic and economic carbon-based dots are easy to produce, but they emit less light. A new study that uses ultrafast nanometric imaging found good and bad emitters among populations of carbon dots. This observation suggests that by selecting only super-emitters, carbon nanodots can be purified to replace toxic metal quantum dots in many applications, the researchers said.

The findings, published in the Proceedings of the National Academy of Sciences, brought together researchers from the University of Illinois Urbana-Champaign and the University of Delaware, Baltimore County in a collaborative project through the Beckman ...

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