Exploring the design of efficient quantum emitters using defects in wide-bandgap semiconductors, specifically silicon carbide (SiC) and diamond.
It highlights how these defects can be engineered to emit single photons, which are crucial for quantum technologies like secure communication and quantum…
Computers benefit greatly from being connected to the internet, so we might ask: What good is a quantum computer without a quantum internet?
Physicists have developed new specialty optical fibers with a micro-structured core to support future quantum computing data transfer needs.
For thousands of years, scholars pondered the question of how anything can move in our world. The problem seemed to have been solved—until the development of quantum mechanics.
Recent advancements in tachyon theory have addressed past inconsistencies by incorporating both past and future states into the boundary conditions, leading to a new quantum entanglement theory and suggesting a critical role for tachyons in matter formation.
Tachyons are hypothetical particles that travel at speeds greater than the speed of light. These superluminal particles, are the “enfant terrible” of modern physics. Until recently, they were generally regarded as entities that did not fit into the special theory of relativity. However, a paper just published by physicists from the University of Warsaw and the University of Oxford has shown that many of these prejudices were unfounded. Tachyons are not only not ruled out by the theory, but allow us to understand its causal structure better.
Superluminal Motion and Tachyons.
The captivating world of quantum mechanics is constantly evolving, revealing complexities that challenge our perception of reality. Recent advancements illuminate the puzzling wave functions of entangled photons, providing remarkable insights into the behavior of these fundamental particles.
At the forefront of this research are experts from the University of Ottawa and Sapienza University of Rome. Their innovative approach allows for real-time visualization of entangled photon wave functions, pushing the boundaries of what we thought possible in quantum science.
Quantum entanglement is a mind-boggling phenomenon that underscores the profound interconnectedness of two particles.
Unlike classical computers, which use bits to process information as either 0s or 1s, quantum computers use quantum bits, also known as qubits, which can represent and process both 0 and 1 simultaneously thanks to a quantum property called superposition. This fundamental difference gives quantum computers the potential to solve some complex problems much more efficiently than classical computers.
INL researcher Ernesto Galvão, in collaboration with Sapienza Università di Roma (Rome) and Istituto di Fotonica e Nanotecnologie (Milan), recently published a groundbreaking study in the journal Science Advances (“Polarization-encoded photonic quantum-to-quantum Bernoulli factory based on a quantum dot source”), where they describe a new set-up for a quantum-to-quantum Bernoulli factory.
A Bernoulli factory is a method to manipulate randomness, using as inputs random coin flips with a certain probability distribution, and outputting coin flips with a different, desired distribution.
Researchers at Purdue University have trapped alkali atoms (cesium) on an integrated photonic circuit, which behaves like a transistor for photons (the smallest energy unit of light) similar to electronic transistors. These trapped atoms demonstrate the potential to build a quantum network based on cold-atom integrated nanophotonic circuits. The team, led by Chen-Lung Hung, associate professor of physics and astronomy at the Purdue University College of Science, published their discovery in the American Physical Society’s Physical Review X (“Trapped Atoms and Superradiance on an Integrated Nanophotonic Microring Circuit”).
“We developed a technique to use lasers to cool and tightly trap atoms on an integrated nanophotonic circuit, where light propagates in a small photonic ‘wire’ or, more precisely, a waveguide that is more than 200 times thinner than a human hair,” explains Hung, who is also a member of the Purdue Quantum Science and Engineering Institute. “These atoms are ‘frozen’ to negative 459.67 degrees Fahrenheit or merely 0.00002 degrees above the absolute zero temperature and are essentially standing still. At this cold temperature, the atoms can be captured by a ‘tractor beam’ aimed at the photonic waveguide and are placed over it at a distance much shorter than the wavelength of light, around 300 nanometers or roughly the size of a virus. At this distance, the atoms can very efficiently interact with photons confined in the photonic waveguide. Using state-of-the-art nanofabrication instruments in the Birck Nanotechnology Center, we pattern the photonic waveguide in a circular shape at a diameter of around 30 microns (three times smaller than a human hair) to form a so-called microring resonator. Light would circulate within the microring resonator and interact with the trapped atoms.”
A key aspect function the team demonstrates in this research is that this atom-coupled microring resonator serves like a ‘transistor’ for photons. They can use these trapped atoms to gate the flow of light through the circuit. If the atoms are in the correct state, photons can transmit through the circuit. Photons are entirely blocked if the atoms are in another state. The stronger the atoms interact with the photons, the more efficient this gate is.
Grasping the precise energy landscapes of quantum particles can significantly enhance the accuracy of computer simulations for material sciences. These simulations are instrumental in developing advanced materials for applications in physics, chemistry, and sustainable technologies. The research tackles longstanding questions from the 1980s, paving the way for breakthroughs across various scientific disciplines.
An international group of physicists, led by researchers at Trinity College Dublin, has developed new theorems in quantum mechanics that explain the “energy landscapes” of quantum particle collections. Their work resolves decades-old questions, paving the way for more accurate computer simulations of materials. This advancement could significantly aid scientists in designing materials poised to revolutionize green technologies.
The new theorems have just been published in the prominent journal Physical Review Letters. The results describe how the energy of systems of particles (such as atoms, molecules, and more exotic matter) changes when their magnetism and particle count change. Solving an open problem important to the simulation of matter using computers, this extends a series of landmark works commencing from the early 1980s.
One of the quantum fields that fills the universe is special because its default value seems poised to eventually change, changing everything.
Scientists from the U.S. Department of Energy’s (DOE) Brookhaven National Laboratory have created the first-ever atomic movies showing how atoms rearrange locally within a quantum material as it transitions from an insulator to a metal. With the help of these movies, the researchers discovered a new material phase that settles a yearslong scientific debate and could facilitate the design of new transitioning materials with commercial applications.