Quantum mechanically entangled groups of eight and ten ultracold atoms provide a critical demonstration for optical-lattice-based quantum processing.
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Quantum processes are helpful to know about when we hear a gimcrack new theory that dismisses or explains away human consciousness. We know it canât just be that simple.
Continue reading “Why Many Researchers Now See the Brain as a Quantum System” »
Graphene nanoribbons have outstanding properties that can be precisely controlled. Researchers from Empa and ETH Zurich, in collaboration with partners from Peking University, the University of Warwick and the Max Planck Institute for Polymer Research, have succeeded in attaching electrodes to individual atomically precise nanoribbons, paving the way for precise characterization of the fascinating ribbons and their possible use in quantum technology.
Quantum technology is promising, but also perplexing. In the coming decades, it is expected to provide us with various technological breakthroughs: smaller and more precise sensors, highly secure communication networks, and powerful computers that can help develop new drugs and materials, control financial markets, and predict the weather much faster than current computing technology ever could.
To achieve this, we need so-called quantum materials: substances that exhibit pronounced quantum physical effects. One such material is graphene. This two-dimensional structural form of carbon has unusual physical properties, such as extraordinarily high tensile strength, thermal and electrical conductivityâas well as certain quantum effects. Restricting the already two-dimensional material even further, for instance, by giving it a ribbon-like shape, gives rise to a range of controllable quantum effects.
Sean Carroll is a theoretical physicist and philosopher who specializes in quantum mechanics, cosmology, and the philosophy of science. He is the Homewood Professor of Natural Philosophy at Johns Hopkins University and an external professor at the Sante Fe Institute. Sean has contributed prolifically to the public understanding of science through a variety of mediums: as an author of several physics books including Something Deeply Hidden and The Biggest Ideas in the Universe, as a public speaker and debater on a wide variety of scientific and philosophical subjects, and also as a host of his podcast Mindscape which covers topics spanning science, society, philosophy, culture, and the arts.
#physics #quantum #philosophy #mathematics.
Trinityâs quantum physicists in collaboration with IBM Dublin have successfully simulated super diffusion in a system of interacting quantum particles on a quantum computer.
This is the first step in doing highly challenging quantum transport calculations on quantum hardware and, as the hardware improves over time, such work promises to shed new light in condensed matter physics and materials science.
Continue reading “Research team simulates super diffusion on a quantum computer” »
Researchers from the Department of Physics at UniversitÀt Hamburg, observed a quantum state that was theoretically predicted more than 50 years ago by Japanese theoreticians but so far eluded detection. By tailoring an artificial atom on the surface of a superconductor, the researchers succeeded in pairing the electrons of the so-called quantum dot, thereby inducing the smallest possible version of a superconductor. The work appears in the journal Nature.
Usually, electrons repel each other due to their negative charge. This phenomenon has a huge impact on many materials properties such as the electrical resistance. The situation changes drastically if the electrons are âgluedâ together to pairs thereby becoming bosons. Bosonic pairs do not avoid each other like single electrons, but many of them can reside at the very same location or do the very same motion.
One of the most intriguing properties of a material with such electron pairs is superconductivity, the possibility to let an electrical current flow through the material without any electrical resistance. For many years, superconductivity has found many important technological applications, including magnetic resonance imaging or highly sensitive detectors for magnetic fields.
A new study led by Vinod M. Menon and his group at the City College of New York shows that trapping light inside magnetic materials may dramatically enhance their intrinsic properties. Strong optical responses of magnets are important for the development of magnetic lasers and magneto-optical memory devices, as well as for emerging quantum transduction applications.
In their new article in Nature, Menon and his team report the properties of a layered magnet that hosts strongly bound excitonsâquasiparticles with particularly strong optical interactions. Because of that, the material is capable of trapping lightâall by itself.
As their experiments show, the optical responses of this material to magnetic phenomena are orders of magnitude stronger than those in typical magnets. âSince the light bounces back and forth inside the magnet, interactions are genuinely enhanced,â said Dr. Florian Dirnberger, the lead-author of the study.
Spin-based sensors have attracted attention due to their high sensitivities. Here authors present a fullerene-based nano spin sensor for in-situ sensing of gas adsorption in porous organic frameworks, demonstrating the potential applications of molecular spin systems in quantum sensing.
Not many pure-play quantum computing start-ups have dared to go public. So far, the financial markets have tended to treat the newcomers unsparingly. One exception is IonQ, who along with D-Wave and Rigetti, reported quarterly earnings last week. Buoyed by hitting key technical and financial goals, IonQâs stock is up ~400% (year-to-date) and CEO Peter Chapman is taking an aggressive stance in the frothy quantum computing landscape where error correction â not qubit count â has increasingly taken center stage as the key challenge.
This is all occurring at a time when a wide variety of different qubit types are vying for dominance. IBM, Google, and Rigetti are betting on superconducting-based qubits. IonQ and Quantinuuum use trapped ions. Atom Computing and QuEra use neutral atoms. PsiQuantum and Xanadu rely on photonics-based qubits. Microsoft is exploring topological qubits based on the rare Marjorana particle. And more are in the works.
Itâs not that the race to scale up qubit-count has ended. IBM has a 433-plus qubit device (Osprey) now and is scheduled to introduce 1100-qubit device (Condor) late this year. Several other quantum computer companies have devices in the 50â100 qubit range. IonQâs latest QPU, Forte, has 32 qubits. The challenge they all face is that current error rates remain so high that itâs impractical to reliably run most applications on the current crop of QPUs.
Researchers have found a way to control the interaction of light and quantum âspinâ in organic semiconductors, that works even at room temperature.
Spin is the term for the intrinsic angular momentum of electrons, which is referred to as up or down. Using the up/down spin states of electrons instead of the 0 and 1 in conventional computer logic could transform the way in which computers process information. And sensors based on quantum principles could vastly improve our abilities to measure and study the world around us.
An international team of researchers, led by the University of Cambridge, has found a way to use particles of light as a âswitchâ that can connect and control the spin of electrons, making them behave like tiny magnets that could be used for quantum applications.
