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Archive for the ‘quantum physics’ category: Page 465

Jun 11, 2021

The rise of integrated quantum photonics

Posted by in categories: computing, quantum physics

Just as microelectronics transformed the modern world through the creation of the integrated circuit, which is now at the heart of most electronic devices, quantum photonics needs an equivalent platform to fulfil its application potential. In this special focus issue of Nature Photonics, we report on the progress in making this a reality with the developments in integrated quantum photonics (IQP).

In a Review Article, Jianwei Wang and colleagues provide a general overview and introduction to IQP circuits and summarize the present development of quantum hardware based on IQP chips. They remark that the challenge for measurement-based quantum computation may shift from the need for deterministic gates to constructing a generic entangled cluster-state, on which any quantum computation could be mapped by a sequence of measurements.

IQP circuits are also a desirable platform for chip-based quantum communications. However, fully integrated chip-based quantum communication has not yet been realized, largely because of the integration difficulties between silicon wafers that feature optical waveguides and other passive components and light sources and photodetectors that are made from different semiconductors. Key components such as transmitters and receivers for quantum key distribution and quantum random number generators are instead individually fabricated.

Jun 11, 2021

Atomistic Simulations of Laser-Controlled Exciton Transfer and Stabilization in Symmetric Double Quantum Dots

Posted by in category: quantum physics

The creation, transfer, and stabilization of localized excitations are studied in a donor–acceptor Frenkel exciton model in an atomistic treatment of reduced-size double quantum dots (QDs) of various sizes. The explicit time-dependent dynamics simulations carried out by hybrid time-dependent density functional theory/configuration interaction show that laser-controlled hole trapping in stacked, coupled germanium/silicon quantum dots can be achieved by a UV/IR pump–dump pulse sequence. The first UV excitation creates an exciton localized on the topmost QD and after some coherent transfer time, an IR pulse dumps and localizes an exciton in the bottom QD. While hole trapping is observed in each excitation step, we show that the stability of the localized electron depends on its multiexcitonic character.

Jun 11, 2021

Messages scrambled by black holes stand their ground against quantum computers

Posted by in categories: cosmology, information science, quantum physics, robotics/AI

Featureless “cost functions” prevent quantum machine learning algorithms from reconstructing scrambled information.

Jun 11, 2021

Researchers build first modular quantum brain sensor, record signal

Posted by in categories: biotech/medical, neuroscience, quantum physics

A team of scientists at the University of Sussex have for the first time built a modular quantum brain scanner, and used it to record a brain signal. This is the first time a brain signal has been detected using a modular quantum brain sensor anywhere in the world. It’s a major milestone for all researchers working on quantum brain imaging technology because modular sensors can be scaled up, like Lego bricks. The team have also connected two sensors like Lego bricks, proving that whole-brain scanning using this method is within reach—as detailed in their paper, which is published today in pre-print. This has not been possible with the currently commercially available quantum brain sensors from the United States.

These modular devices work like play bricks in that they can be connected together. This opens up the potential for whole– scanning using quantum technology, and potential advances for neurodegenerative diseases like Alzheimer’s.

The device, which was built at the Quantum Systems and Devices laboratory at the university, uses ultra-sensitive quantum to pick up these tiniest of magnetic fields to see inside the brain in order to map the neural activity.

Jun 11, 2021

Researchers observe sound-light pulses in 2D materials for the first time

Posted by in categories: computing, engineering, particle physics, quantum physics

Using an ultrafast transmission electron microscope, researchers from the Technion—Israel Institute of Technology have, for the first time, recorded the propagation of combined sound and light waves in atomically thin materials.

The experiments were performed in the Robert and Ruth Magid Electron Beam Quantum Dynamics Laboratory headed by Professor Ido Kaminer, of the Andrew and Erna Viterbi Faculty of Electrical & Computer Engineering and the Solid State Institute.

Continue reading “Researchers observe sound-light pulses in 2D materials for the first time” »

Jun 11, 2021

Physicists link quantum memories in early step toward quantum internet

Posted by in categories: internet, quantum physics

Two novel demonstrations bring the backbone of the quantum internet, quantum repeaters, a little closer.

Jun 11, 2021

Seraphim Capital unveils worlds first listed space technology fund

Posted by in categories: encryption, quantum physics, space

TAMPA, Fla. — Seraphim Capital plans to trade stakes it has amassed in space technology startups on the public market through an investment trust.

The Seraphim Space Investment Trust will eventually comprise bets in 19 international startups, including satellite data specialist Spire Global, quantum encryption firm Arqit and space-based cellular network operator AST Space Mobile.

Those three recently got valuations of more than $1 billion in mergers with special purpose acquisition companies (SPACs), investment vehicles that offer another route to public markets.

Jun 11, 2021

Say goodbye to your camera bump: Miniaturized optics through new counterpart to lens

Posted by in categories: mobile phones, quantum physics, space

ANOTHER OPTICAL BREAKTHROUGH COMPLEMENTING METALENSES. In addition to the ongoing revolution in optical science brought about by flat metalenses and single-photon image sensors, there is another parallel and complementing new dimension now added to the mix, which, according to this article, will allow telescopes as thin as a piece of paper.


Can you imagine one day using a telescope as thin as a sheet of paper, or a much smaller and lighter high-performance camera? Or no longer having that camera bump behind your smartphone?

In a paper published in Nature Communications, researchers from the University of Ottawa have proposed a new optical element that could turn these ideas into reality by dramatically miniaturizing optical devices, potentially impacting many of the applications in our lives.

Continue reading “Say goodbye to your camera bump: Miniaturized optics through new counterpart to lens” »

Jun 10, 2021

Researchers create an un-hackable quantum network over hundreds of kilometers using optical fiber

Posted by in categories: cybercrime/malcode, quantum physics

Toshiba’s research team has broken a new record for optical fiber-based quantum communications, thanks to a new technology called dual band stabilization.

Jun 10, 2021

Hacking bitcoin wallets with quantum computers could happen – but cryptographers are racing to build a workaround

Posted by in categories: bitcoin, cybercrime/malcode, mobile phones, quantum physics

Stefan Thomas really could have used a quantum computer this year.

The German-born programmer and crypto trader forgot the password to unlock his digital wallet, which contains 7002 bitcoin, now worth $265 million. Quantum computers, which will be several million times faster than traditional computers, could have easily helped him crack the code.

Though quantum computing is still very much in its infancy, governments and private-sector companies such as Microsoft and Google are working to make it a reality. Within a decade, quantum computers could be powerful enough to break the cryptographic security that protects cell phones, bank accounts, email addresses and — yes — bitcoin wallets.