Science Daily October 23, 2019 Using 53 entangled qubits an international team of researchers (USA – Google, UMass Amherst, NASA, Caltech, UC Santa Barbara, Oak Ridge National Laboratory, UC Riverside, industry, Germany) has solved a problem that would take 10,000 years on a classical supercomputer in 200 seconds on their quantum computer. The algorithm was chosen to emphasize the strengths of the quantum computer by leveraging the natural dynamics of the device. They used a method called cross-entropy benchmarking to compare the quantum circuit’s output (a “bitstring”) to its corresponding ideal probability computed via simulation on a classical computer to […]
Tag Archives: Quantum science
Solving the mystery of quantum light in thin layers
Science Daily October 15, 2019 Single-photon emitters play a key role in present and emerging quantum technologies. Several recent measurements have established monolayer WSe2 as a promising candidate for a reliable single-photon source. Researchers in Austria have shown that the origin and underlying microscopic processes responsible for this quantum light effect are the subtle interaction of single atomic defects in the material and mechanical strain. Computer simulations show how the electrons are driven to specific places in the material, where they are captured by a defect, lose energy and emit a photon…read more. TECHNICAL ARTICLE
Weaving quantum processors out of laser light
Science Daily October 17, 2019 The approach taken by an international team of researchers (Japan, Australia, USA – University of New Mexico) starts with extreme scalability, built in from the very beginning, because the processor, called a cluster state is made of light. A cluster state is a large collection of entangled quantum components that performs quantum computations when measured in a particular way. To be useful for real-world problems, a cluster state must be both large enough and have the right entanglement structure. To make the cluster state, specially designed crystals convert ordinary laser light into quantum light called […]
Creating a single phonon in ambient conditions
Nanowerk October 8, 2019 So far, individual phonons have only been observed at extremely low temperatures and under high vacuum. An international team of researchers (Switzerland, USA – MIT) shot ultrafast laser pulses onto a diamond crystal to excite its atomic lattice into vibrating. By careful design of the experiment, they triggered a collective vibration involving more than 100 billion atoms that exchanged energy with single photons from the laser light. By measuring the energy exchanged by this vibration with single photons, they were able to prove that a single phonon was excited, and confirm that the collective oscillation behaves […]
Physicists couple key components of quantum technologies
EurekAlert October 9, 2019 Researchers in Germany developed an interface that couples light sources for single photons with nanophotonic networks. They considered quantum emitters which are embedded in nanodiamonds and emit photons when they are stimulated by means of electromagnetic fields. In order to produce the desired interfaces, they aimed to develop optical structures tailored to the wavelength of the quantum emitters. In structuring the crystals, they varied not only the size and the arrangement of the cavities, but also the width of the waveguide on which the cavities were placed. They found photonic crystals which demonstrated a special variation […]
Can we peek at Schrodinger’s cat without disturbing it?
Science Daily October 2, 2019 According to an international team of researchers (Japan, India) a camera set up outside a box that has Schrödinger’s cat takes a photo of the cat, and the scientists don’t know whether it is dead or alive. The flash from the camera has removed a “quantum tag” marking the superposition of the cat. The photo is now entangled with the fate of the cat i.e. we can decide what happened to the cat by processing this photo in a certain way. The researchers propose that depending on what method is used to process the photo, […]
Delivering on Quantum Innovation
IEEE Spectrum September 13, 2019 The University of Maryland has announced the launch of the Quantum Technology Center which aims to translate quantum physics research into innovative technologies. The center will pursue collaborations with industry and government labs to help take promising quantum advances from the lab to the marketplace. It will also train students in the development and application of quantum technologies to produce a workforce educated in quantum-related engineering. UMD already hosts more than 200 researchers in quantum science, one of the greatest concentrations in the world. Much of the effort has been led by the Joint Quantum […]
Uncovering the hidden “noise” that can kill qubits
MIT News September 16, 2019 Statistics-based models to estimate the impact of unwanted noise sources surrounding qubits to create new ways to protect them generally capture simplistic Gaussian noise. A team of researchers (MIT, Dartmouth College) developed a technique to separate non-Gaussian noise from the background Gaussian noise, and then used signal-processing techniques to reconstruct highly detailed information about those noise signals. The key innovation behind the work is carefully engineering the pulses to act as specific filters that extract properties of the “bispectrum,” a two-dimension representation that gives information about distinctive time correlations of non-Gaussian noise. Those reconstructions can […]
Scientists discover new state of matter
Phys.org August 15, 2019 A team of researchers in the US (New York University, Wayne State University, SUNY Buffalo) have shown the experimental evidence for a topological superconductivity. They analyzed a transition of quantum state from its conventional state to a new topological state, measuring the energy barrier between these states focusing on majorana particles. Majorana particles have the potential to store quantum information in a special computation space where quantum information is protected from the environment noise. As there is no natural host material for these particles the new form of matter provides a platform on which these calculations […]
Physicists use light waves to accelerate supercurrents, enable ultrafast quantum computing
Science Daily July 1, 2019 A team of researchers in the US (Iowa State University, University of Wisconsin, University of Alabama at Birmingham) is finding new macroscopic supercurrent flowing states and developing quantum controls for switching and modulating them. Experimental data obtained from a terahertz spectroscopy instrument indicates terahertz light-wave tuning of supercurrents is a universal tool and key for pushing quantum functionalities to reach their ultimate limits in many cross-cutting disciplines, design of emergent materials properties and collective coherent oscillations for quantum engineering applications…read more. TECHNICAL ARTICLES