However, if long and thin strips of graphene (termed graphene nanoribbons) are cut out of a wide graphene sheet, the quantum charge carriers become confined within the narrow dimension, which makes them semi-conducting and enables their use in quantum switching devices. As of today, there are a number of barriers to using graphene nanoribbons in devices, among them is the challenge of reproducibly growing narrow and long sheets that are isolated from the environment.
In this new study, the researchers were able to develop a method to catalytically grow narrow, long, and reproducible graphene nanoribbons directly within insulating hexagonal boron-nitride stacks, as well as demonstrate peak performance in quantum switching devices based on the newly-grown ribbons. The unique growth mechanism was revealed using advanced molecular dynamics simulation tools that were developed and implemented by the Israeli teams.
These calculations showed that ultra-low friction in certain growth directions within the boron-nitride crystal dictates the reproducibility of the structure of the ribbon, allowing it to grow to unprecedented lengths directly within a clean and isolated environment.
Scientists have discovered that a “single atomic defect” in a layered 2D material can hold onto quantum information for microseconds at room temperature, underscoring the potential of 2D materials in advancing quantum technologies.
The defect, found by researchers from the Universities of Manchester and Cambridge using a thin material called hexagonal boron nitride (hBN), demonstrates spin coherence—a property where an electronic spin can retain quantum information —under ambient conditions. They also found that these spins can be controlled with light.
Up until now, only a few solid-state materials have been able to do this, marking a significant step forward in quantum technologies.
Quantum information science is truly fascinating—pairs of tiny particles can be entangled such that an operation on either one will affect them both even if they are physically separated. A seemingly magical process called teleportation can share information between different far-flung quantum systems.
A new study unveils the existence of a tetraquark composed of beauty and charm quarks, advancing our knowledge of subatomic particle physics and strong force interactions.
Exploring the complex domain of subatomic particles, researchers at The Institute of Mathematical Science (IMSc) and the Tata Institute of Fundamental Research (TIFR) have recently published a novel finding in the journal Physical Review Letters. Their study illuminates a new horizon within Quantum Chromodynamics (QCD), shedding light on exotic subatomic particles and pushing the boundaries of our understanding of the strong force.
If you zoom in on a chemical reaction to the quantum level, you’ll notice that particles behave like waves that can ripple and collide. Scientists have long sought to understand quantum coherence, the ability of particles to maintain phase relationships and exist in multiple states simultaneously; this is akin to all parts of a wave being synchronized. It has been an open question whether quantum coherence can persist through a chemical reaction where bonds dynamically break and form.
Now, for the first time, a team of Harvard scientists has demonstrated the survival of quantum coherence in a chemical reaction involving ultracold molecules. These findings highlight the potential of harnessing chemical reactions for future applications in quantum information science.
“I am extremely proud of our work investigating a very fundamental property of a chemical reaction where we really didn’t know what the result would be,” said senior co-author Kang-Kuen Ni, Theodore William Richards Professor of Chemistry and Professor of Physics. “It was really gratifying to do an experiment to find out what Mother Nature tells us.”
A team led by Chen Xianhui and Professor Xiang Ziji from the CAS Key Laboratory of Strongly-Coupled Quantum Matter Physics and the Department of Physics at the University of Science and Technology of China, uncovered a unique superconducting state characterized by one-dimensional superconducting stripes. This state is induced by the ferromagnetic proximity effect in an oxide heterostructure made up of ferromagnetic EuO and (110)-oriented KTaO3 (KTO). Their findings were published in Nature Physics.
The academic community concurs that the emergence of unconventional superconducting pairings is intricately linked to magnetism, particularly in copper oxides and iron-based high-temperature superconductors. Magnetic fluctuations are deemed pivotal in the genesis of high-temperature superconductivity, where the interplay between superconductivity and magnetism gives rise to superconducting states exhibiting unique spatial modulation. Superconducting oxide heterostructures encompassing magnetic structural units emerge as an optimal platform for investigating such superconducting states.
Building upon their prior achievements, the research team delved deeper into the superconductivity of this system and its relationship with the ferromagnetic proximity effect, meticulously adjusting the carrier concentration of the two-dimensional electron gas residing at the interface. They uncovered an intriguing in-plane anisotropy in superconductivity among samples with low carrier concentrations, which nevertheless vanished in samples exhibiting higher carrier concentrations.
Recent discoveries in quantum physics have revealed simpler atomic structures than hydrogen, involving pure electromagnetic interactions between particles like electrons and their antiparticles. This advancement has significant implications for our understanding of quantum mechanics and fundamental physics, highlighted by new methods for detecting tauonium, which could revolutionize measurements of particle physics.
The hydrogen atom was once considered the simplest atom in nature, composed of a structureless electron and a structured proton. However, as research progressed, scientists discovered a simpler type of atom, consisting of structureless electrons (e-), muons (μ-), or tauons (τ-) and their equally structureless antiparticles. These atoms are bound together solely by electromagnetic interactions, with simpler structures than hydrogen atoms, providing a new perspective on scientific problems such as quantum mechanics, fundamental symmetry, and gravity.
Discovery of Electromagnetic Interaction Atoms.