Science Daily May 7, 2020 An international team of researchers (Switzerland, Germany) used laser light to couple the vibrations of a 100 nanometer thin membrane to the motion of the spin of atoms over a distance of one meter. As a result, each vibration of the membrane sets the spin of the atoms in motion and vice versa. In this laser loop, the properties of the light can be controlled such that no information about the motion of the two systems is lost to the environment, thus ensuring that the quantum mechanical interaction is not disturbed. It is possible to […]
Tag Archives: Quantum communications
World’s First “Quantum Drone” for Impenetrable Air-to-Ground Data Links Takes Off
IEEE Spectrum June 18, 2019 Researchers in China have developed an eight-rotor octocopter drone whose 35-kilogram weight at takeoff, includes its onboard quantum communication system. The quantum drone can operate while hovering in midair for 40 minutes at a time. It can maintain two air-to-ground links, each roughly 100 meters long, and can receive and transmit entangled photons during the daytime, on a clear night, and even on a rainy night. According to some scientists a communications network featuring quantum drones could be stymied by a number of challenges such as photons scattering, absorbed, or otherwise lost on their way […]
Scientists move quantum optic networks a step closer to reality
Nanowerk January 2, 2019 A team of researchers in the US (Argonne National Laboratory, University of Chicago, Northwestern University) found that absorption dipoles in individual quasi-two-dimensional nanoplatelets are isotropic in three dimensions at the excitation wavelength. Emission anisotropy can be readily explained by the electric field renormalization effect caused by the dielectric contrast between the NPLs and the surrounding medium. They concluded that emission dipoles in NPLs are isotropic in the plane of the NPLs. The findings present an approach for disentangling the effects of dipole degeneracy and electric field renormalization on emission anisotropy and can be adapted for studying […]
The man turning China into a quantum superpower
MIT Technology Review December 19, 2018 An international team of scientists (Austria, China) made possible an unhackable videoconference between Vienna and Beijing. They include a plan to create a globe-spanning constellation of satellites that constitute a super-secure quantum internet. As funding for government programs is opaque, it could be $1.1 billilon. In spite of this China still trails the US in quantum computing. If China thinks the technology could give it a military edge, it might pull back on international collaborations and keep innovations to itself. Close coordination between Chinese government research groups, the Chinese Academy of Sciences, and the […]
On-demand room-temperature single photon array—a quantum communication breakthrough
Phys.org September 21, 2018 An international team of researchers (USA – City College of New York, Australia, Lithuania) has demonstrated large arrays of room-temperature quantum emitters in two-dimensional hexagonal boron nitride. The large energy gap inherent in substrate-induced deformation in hBN stabilizes the emitters at room temperature within nanoscale regions. Combining analytical and numerical modeling, they showed that emitter activation is the result of carrier trapping in deformation potential wells. The breakthrough has solved a long-standing and practical hurdle of realizing deterministic single photon emitters at room temperature… read more. Open Access TECHNICAL ARTICLE
New study could hold key to hack-proof systems
Phys.org July 17, 2018 An international team of researchers (Austria, France, Czech Republic, Slovakia, Switzerland, Spain, UK) show how carefully constructed measurements in two bases (one of which is not orthonormal) can be used to faithfully and efficiently certify bipartite high-dimensional states and their entanglement for any physical platform. In an experimental set-up, they were able to verify 9-dimensional entanglement for a pair of photons on a 11-dimensional subspace each. The group is currently looking into a more direct use of this technique in actual quantum cryptography protocols and expect their technique to be widely applied in other quantum systems […]
A Step Toward Quantum Repeaters
Optics and Photonics July 6, 2018 An international team of researchers (USA – Princeton University, Gemological Institute of America, UK) reports a color center that shows insensitivity to environmental decoherence caused by phonons and electric field noise: the neutral charge state of silicon vacancy (SiV0). Through careful materials engineering, they achieved >80% conversion of implanted silicon to SiV0. SiV0 exhibits spin-lattice relaxation times approaching 1 minute and coherence times approaching 1 second. Its optical properties are very favorable, with ~90% of its emission into the zero-phonon line and near–transform-limited optical linewidths. These combined properties make SiV0 a promising defect for […]