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Archive for the ‘quantum physics’ category: Page 5

Dec 11, 2024

Google says its new quantum chip indicates that multiple universes exist

Posted by in categories: computing, cosmology, quantum physics

Google on Monday announced Willow, its latest, greatest quantum computing chip. The speed and reliability performance claims Google’s made about this chip were newsworthy in themselves, but what really caught the tech industry’s attention was an even wilder claim tucked into the blog post about the chip.

Google Quantum AI founder Hartmut Neven wrote in his blog post that this chip was so mind-boggling fast that it must have borrowed computational power from other universes.

Ergo the chip’s performance indicates that parallel universes exist and “we live in a multiverse.”

Dec 11, 2024

Quantum computing’s next step: New algorithm boosts multitasking

Posted by in categories: computing, information science, quantum physics

Quantum computers differ fundamentally from classical ones. Instead of using bits (0s and 1s), they employ “qubits,” which can exist in multiple states simultaneously due to quantum phenomena like superposition and entanglement.

For a quantum computer to simulate dynamic processes or process data, among other essential tasks, it must translate complex input data into “quantum data” that it can understand. This process is known as quantum compilation.

Essentially, quantum compilation “programs” the quantum computer by converting a particular goal into an executable sequence. Just as the GPS app converts your desired destination into a sequence of actionable steps you can follow, quantum compilation translates a high-level goal into a precise sequence of quantum operations that the quantum computer can execute.

Dec 11, 2024

Could Recent Discoveries in Gravity Fundamentally Change Physics?

Posted by in categories: cosmology, particle physics, quantum physics, satellites

For centuries, gravity has been one of the most captivating and puzzling forces in the universe. Thanks to the groundbreaking work of Isaac Newton and Albert Einstein, we have a robust understanding of how gravity governs the behavior of planets, stars, and even galaxies. Yet, when we look at extreme scenarios, such as the intense gravitational fields near black holes or the mysterious quantum world, our understanding starts to break down. New research and theories, however, suggest that the key to solving these mysteries may finally be within reach.

In our daily lives, gravity is a constant presence. It’s what keeps us grounded to the Earth, dictates the orbits of planets, and ensures that satellites stay in orbit around our planet. Thanks to Einstein’s general theory of relativity, scientists have been able to make highly accurate predictions about the movement of celestial bodies, calculate tides, and even send probes to the farthest reaches of the solar system.

Yet, when gravity’s effects become more extreme—such as inside black holes or during the birth of the universe—it becomes much more difficult to model. Similarly, when we turn our attention to the quantum realm of subatomic particles, Einstein’s theory breaks down. To understand phenomena like the Big Bang or the inner workings of black holes, physicists have long known that we need a new, unified theory of gravity.

Dec 11, 2024

Google DeepMind’s Breakthrough “AlphaQubit” Closing in on the Holy Grail of Quantum Computing

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

The dream of building a practical, fault-tolerant quantum computer has taken a significant step forward.

In a breakthrough study recently published in Nature, researchers from Google DeepMind and Google Quantum AI said they have developed an AI-based decoder, AlphaQubit, which drastically improves the accuracy of quantum error correction—a critical challenge in quantum computing.

“Our work illustrates the ability of machine learning to go beyond human-designed algorithms by learning from data directly, highlighting machine learning as a strong contender for decoding in quantum computers,” researchers wrote.

Dec 11, 2024

Ultrafast Control of Nonlinear Hot Dirac Electrons in Graphene: An International Collaboration

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

Nonlinear optics explores how powerful light (e.g. lasers) interacts with materials, resulting in the output light changing colour (i.e. frequency) or behaving differently based on the intensity of the incoming light. This field is crucial for developing advanced technologies such as high-speed communication systems and laser-based applications. Nonlinear optical phenomena enable the manipulation of light in novel ways, leading to breakthroughs in fields like telecommunications, medical imaging, and quantum computing. Two-dimensional (2D) materials, such as graphene—a single layer of carbon atoms in a hexagonal lattice—exhibit unique properties due to their thinness and high surface area. Graphene’s exceptional electronic properties, related to relativistic-like Dirac electrons and strong light-matter interactions, make it promising for nonlinear optical applications, including ultrafast photonics, optical modulators, saturable absorbers in ultrafast lasers, and quantum optics.

Dr. Habib Rostami, from the Department of Physics at the University of Bath, has co-authored pioneering research published in Advanced Science. This study involved an international collaboration between an experimental team at Friedrich Schiller University Jena in Germany and theoretical teams at the University of Pisa in Italy and the University of Bath in the UK. The research aimed to investigate the ultrafast opto-electronic and thermal tuning of nonlinear optics in graphene.

This study discovers a new way to control high-harmonic generation in a graphene-based field-effect transistor. The team investigated the impact of lattice temperature, electron doping, and all-optical ultrafast tuning of third-harmonic generation in a hexagonal boron nitride-encapsulated graphene opto-electronic device. They demonstrated up to 85% modulation depth along with gate-tuneable ultrafast dynamics, a significant improvement over previous static tuning. Furthermore, by changing the lattice temperature of graphene, the team could enhance the modulation of its optical response, achieving a modulation factor of up to 300%. The experimental fabrication and measurement took place at Friedrich Schiller University Jena. Dr. Rostami played a crucial role in the study by crafting theoretical models. These models were developed in collaboration with another theory team at the University of Pisa to elucidate new effects observed in graphene.

Dec 11, 2024

Rethinking the quantum chip: Engineers present new design for superconducting quantum processor

Posted by in categories: computing, engineering, quantum physics

Researchers at the UChicago Pritzker School of Molecular Engineering (UChicago PME) have realized a new design for a superconducting quantum processor, aiming at a potential architecture for the large-scale, durable devices the quantum revolution demands.

Unlike the typical quantum chip design that lays the information-processing qubits onto a 2D grid, the team from the Cleland Lab has designed a modular quantum processor comprising a reconfigurable router as a central hub. This enables any two qubits to connect and entangle, where in the older system, qubits can only talk to the qubits physically nearest to them.

“A quantum computer won’t necessarily compete with a classical computer in things like memory size or CPU size,” said UChicago PME Prof. Andrew Cleland.

Dec 11, 2024

Scientists develop cost-effective lasers for extended short-wave infrared applications

Posted by in categories: chemistry, computing, quantum physics

Current laser technologies for the extended short-wave infrared (SWIR) spectral range rely on expensive and complex materials, limiting their scalability and affordability. To address these challenges, ICFO researchers have presented a novel approach based on colloidal quantum dots in an Advanced Materials article. The team managed to emit coherent light (a necessary condition to create lasers) in the extended SWIR range with large colloidal quantum dots made of lead sulfide (PbS).

This new CQD-based technology offers a solution to the aforementioned challenges while maintaining compatibility with silicon CMOS platforms (the technology used for constructing integrated circuit chips) for on-chip integration.

Their PbS colloidal quantum dots are the first semiconductor lasing material to cover such a broad wavelength range. Remarkably, the researchers accomplished this without altering the dots’ chemical composition. These results pave the way towards the realization of more practical and compact lasers.

Dec 11, 2024

Alena Tensor—a new hope for unification in physics

Posted by in categories: mathematics, quantum physics

The search for quantum gravity has gone on for 100 years, but it is not the only unification challenge in physics. Many of us believe that one day there will be a unification theory—a theory that will reconcile many divergent physical theories.

Our new article published in Physica Scripta brings new hope that such a theory exists. It demonstrates that the use of a certain mathematical object called Alena Tensor reconciles various physical theories, including , electrodynamics, and continuum mechanics. Will this finally allow scientists to unify descriptions used in physics?

Dec 11, 2024

Room-temperature nanodevice that generates structured light shows promise for secure communication and advanced optics

Posted by in categories: innovation, quantum physics

Researchers have developed a tiny, room-temperature device that creates a special type of structured light called radially polarized photons, which are highly useful for secure communication, advanced imaging, and precision optical tools.

By carefully designing and positioning a quantum dot within a nanoantenna, they achieved high-quality light with more than 93% purity. This breakthrough helps improve the efficiency and practicality of devices that use structured light, paving the way for advancements in and optical technology.

A team led by Prof. Ronen Rapaport from the Racah School of Physics at The Hebrew University of Jerusalem has developed the new device that produces radially polarized photons at room temperature. This advancement offers new possibilities for both classical and quantum communication technologies.

Dec 11, 2024

Colloidal quantum dots enable tunable liquid-state lasers

Posted by in category: quantum physics

Present-day liquid-state lasers are based on organic dyes. Here we demonstrate an alternative class of liquid lasers that use solutions of colloidal quantum dots (QDs). Previous efforts to realize such devices have been hampered by the fast non-radiative Auger recombination of multicarrier states required for optical gain. Here we overcome this challenge by using type-(I + II) QDs, which feature a trion-like optical gain state with strongly suppressed Auger recombination. When combined with a Littrow optical cavity, static (non-circulated) solutions of these QDs exhibit stable lasing tunable from 634 nm to 575 nm. These results indicate the feasibility of technologically viable dye-like QD lasers that exhibit broad spectral tunability and, importantly, provide stable operation without the need for a circulation system—a standard attribute of traditional dye lasers. The latter opens the door to less complex and more compact devices that can be readily integrated with various optical and electro-optical systems. An additional advantage of these lasers is the wide range of potentially available wavelengths that can be selected by controlling the composition, size and structure of the QDs.


Liquid lasers based on solutions of colloidal quantum dots exhibit a trion-like optical gain state with suppressed Auger recombination, which combined with a Littrow optical cavity enables stable and tunable liquid-state lasing.

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