Physicists at the University of Cologne have taken an important step forward in the pursuit of topological quantum computing by demonstrating the first-ever observation of Crossed Andreev Reflection (CAR) in topological insulator (TI) nanowires.
This finding, published under the title “Long-range crossed Andreev reflection in topological insulator nanowires proximitized by a superconductor” in Nature Physics, deepens our understanding of superconducting effects in these materials, which is essential for realizing robust quantum bits (qubits) based on Majorana zero-modes in the TI platform—a major goal of the Cluster of Excellence Matter and Light for Quantum Computing (ML4Q).
Quantum computing promises to revolutionize information processing, but current qubit technologies struggle with maintaining stability and error correction. One of the most promising approaches to overcoming these limitations is the use of topological superconductors, which can host special quantum states called Majorana zero-modes.
Once described by Einstein as “spooky action at a distance,” quantum entanglement may now seem less intimidating in light of new research findings.
Osaka Metropolitan University physicists have developed new, simpler formulas to quantify quantum entanglement in strongly correlated electron systems and applied them to study several nanoscale materials. Their results offer fresh perspectives into quantum behaviors in materials with different physical characteristics, contributing to advances in quantum technologies.
Predictions of theories that combine quantum mechanics with gravity could be observed using highly sensitive photon detection in a tabletop experiment.
Quantum-gravity theories attempt to unite gravity and quantum mechanics. A proposed tabletop experiment called Gravity from the Quantum Entanglement of Space Time (GQuEST) would search for a predicted effect of such theories using a new type of interferometer—one that counts photons rather than measuring interference patterns. The GQuEST team has now calculated the sensitivity of their design and shown that it can recover the predicted signal 100 times faster than traditional interferometer setups [1].
Quantizing gravity implies that spacetime is not continuous—it becomes “pixelated” when you look at scales as small as 10−35 m, far too small to be probed in any experiment. However, certain quantum-gravity models predict that spacetime can fluctuate—a kind of spontaneous stretching and squeezing in the spacetime fabric that might produce observable effects [2]. “You couldn’t detect a single pixel, but you could detect the coherent fluctuations of many pixels,” says Caltech theorist Kathryn Zurek. She has formulated a “pixellon” model, which predicts that collective fluctuations inside an interferometer can cause a detectable frequency change, or modulation, in the interferometer’s output light [3].
If gravity arises from entropy, scientists could unite Einstein’s general relativity with the quantum realm while shedding light on dark matter and dark energy.
China’s Zuchongzhi-3 ignites a fierce quantum race with Google’s Willow, pushing quantum singularity from theory toward reality faster than skeptics predicted.
Buy me a coffee and support the channel: https://ko-fi.com/jkzero. Part 3 of the groundbreaking but less-known theory of quantum mechanics proposed by Louis de Broglie in 1923. In this video de Broglie’s unification of wave and particles using his matter waves to show that Fermat’s principle of ray optics is equivalent to Maupertuis’ principle for the dynamics of particles. Although incomplete, this corresponds to the early development of de Broglie’s pilot-wave theory.
∘ L. de Broglie, “Ondes et quanta,” Comptes Rendus Hebdomadaires des Séances de l’Aadémie des Sciences (Paris), 177,507 (1923) ∘ L. de Broglie, “Quanta de lumière, diffraction et interférences,” Comptes Rendus Hebdomadaires des Séances de l’Aadémie des Sciences (Paris), 177,548 (1923) ∘ L. de Broglie, “Les quanta, la théorie cinétique des gaz et le principe de Fermat,” Comptes Rendus Hebdomadaires des Séances de l’Aadémie des Sciences (Paris), 177,630 (1923) ∘ F. Grimaldi, “Physico-mathesis de lumine, coloribus et iride aliisque adnexis” (1665) ∘ I. Newton, “Optiks” (1704) ∘ L. de Broglie, “On the Theory of Quanta,” translation of doctoral thesis, Foundation Louis De Broglie (1924) ∘ A. Einstein, “Quantum theory of the monatomic ideal gas, Part II” Sitzungsber. Preuss. Akad. Wiss. 3, (1925)
M. de Broglie, public domain. Diffraction half plane with rays, by MikeRun under CC BY-SA 4.0 Oualidia Lagoon, Morocco via Google Earth. Matter Waves, AT&T Archives and History Center (1961) Francesco Grimaldi, public domain. First edition of Opticks, public domain. Isaac Newton by Sir Godfrey Kneller, public domain. Light refraction, by ajizai, public domain. Interference pattern, by J.S. Diaz (own work) Polarization clamp, by A.Davidhazy under CC BY-SA 4.0 Light bulb through diffraction grating, by R.D. Anderson under CC BY-SA 3.0 Davisson and Germer, public domain. Davisson-Germer Figure 2, public domain. Fifth Solvay Conference, AIP Refraction with soda straw, by Bcrowell under CC BY-SA 1.0 Pierre Louis Moreau de Maupertuis, public domain. P. Langevin, public domain. Peter Debye, AIP Portrait of Erwin Schrodinger, AIP Eels Swimming in Aquarium by M. Ehlers, free use via Pexels https://www.pexels.com/video/eels-swimming-in-aquarium-10106765/
Real-space quantum vortices are key to many phenomena in modern physics. New experiments provide the first proof of vortices in momentum space, raising the prospect of exploring novel orbitronic phenomena.
Dissolving polymers with organic solvents is the essential process in the research and development of polymeric materials, including polymer synthesis, refining, painting, and coating. Now more than ever recycling plastic waste is a particularly imperative part of reducing carbon produced by the materials development processes.
Polymers, in this instance, refer to plastics and plastic-like materials that require certain solvents to be able to effectively dissolve and therefore become recyclable, though it’s not as easy as it sounds. Utilizing Mitsubishi Chemical Group’s (MCG) databank of quantum chemistry calculations, scientists developed a novel machine learning system for determining the miscibility of any given polymer with its solvent candidates, referred to as χ (chi) parameters.
This system has enabled scientists to overcome the limitations arising from a limited amount of experimental data on the polymer-solvent miscibility by integrating massive data produced from the computer experiments using high-throughput quantum chemistry calculations.
Microwaves are usually used to interact with superconducting qubits, but optical photons can be processed at room temperature. The electro-optical transceiver presented here allows all-optical readout of a qubit without affecting its performance.
