Science Daily February 5, 2018 Using computational simulations, an international team of researchers (USA – Northwestern University, Austria, Germany, China) discovered coexisting quantum-mechanical interactions in the compound silver-bismuth-oxide. Bismuth enables the spin of the electron to interact with its own motion and does not exhibit inversion symmetry. By applying an electric field to the material, researchers were able to control whether the electron spins were coupled in pairs or separated as well as whether the system is electrically conductive or not. The findings could enable ultrafast, low-power electronics and quantum computers that operate faster than current models… read more. Open Access […]
Category Archives: Quantum science
Job One for Quantum Computers: Boost Artificial Intelligence
Quanta Magazine January 29, 2018 The fusion of quantum computing and machine learning has become a booming research area. Can it possibly live up to its high expectations? Although one might think a quantum machine-learning system should be powerful, it suffers from a kind of locked-in syndrome. It operates on quantum states, not on human-readable data, and translating between the two can negate its apparent advantages… read more.
What’s the noise eating quantum bits?
Phys.org January 8, 2018 The ability to develop SQUID-based quantum computers will require the stored magnetic data survive for long times. Theory calculations by a team of researchers in the US (University of Wisconsin–Madison, Argonne National Laboratory, UC Irvine, NIST-Colorado), showed that adsorbed molecular oxygen on the surfaces is the dominant contributor to magnetic noise for superconducting niobium and aluminum thin films. They found that surface treatment with ammonia and improving the sample vacuum environment dramatically reduced the surface contamination (to less than one oxygen molecule per 10 nm2), minimizing magnetic noise. Their work provides a design strategy for the […]
Quantum simulators wield control over more than 50 qubits, setting new record
Source: Science Daily, November 29, 2017 Two independent teams of researchers in the US (University of Maryland, NIST) and (Harvard University, MIT) have used more than 50 interacting atomic qubits to mimic magnetic quantum matter. UMD-NIST team deployed ytterbium ions trapped in place by gold-coated and razor-sharp electrodes and Harvard-MIT team used rubidium atoms confined by an array of laser beams. In this experiment there are over a quadrillion possible magnet configurations, and this number doubles with each additional magnet. Quantum simulations are believed to be one of the first useful applications of quantum computers. After perfecting these quantum simulators, […]
Single-photon detector can count to 4
Source: Nanowerk December 15,2017 A team of researchers in the US (Duke University, Ohio State University, industry) used the superconducting nanowire single-photon detector (SNSPD) method to show multi-photon detection indicating number resolution up to four photons. They paid special attention to the specific shape of the initial spike in the electrical signal to correctly count at least four photons traveling together in a packet. Photon-number-resolution is very useful for a lot of quantum information/communication and quantum optics experiment; it could greatly increase the speed of quantum encryption techniques… read more. Open Access TECHNICAL ARTICLE