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Mechanical systems facilitate the development of a hybrid quantum technology comprising electrical, optical, atomic and acoustic degrees of freedom, and entanglement is essential to realize quantum-enabled devices. Continuous-variable entangled fields—known as Einstein–Podolsky–Rosen (EPR) states—are spatially separated two-mode squeezed states that can be used for quantum teleportation and quantum communication. In the optical domain, EPR states are typically generated using nondegenerate optical amplifiers, and at microwave frequencies Josephson circuits can serve as a nonlinear medium^4,5,6. An outstanding goal is to deterministically generate and distribute entangled states with a mechanical oscillator, which requires a carefully arranged balance between excitation, cooling and dissipation in an ultralow noise environment. Here we observe stationary emission of path-entangled microwave radiation from a parametrically driven 30-micrometre-long silicon nanostring oscillator, squeezing the joint field operators of two thermal modes by 3.40 decibels below the vacuum level. The motion of this micromechanical system correlates up to 50 photons per second per hertz, giving rise to a quantum discord that is robust with respect to microwave noise. Such generalized quantum correlations of separable states are important for quantum-enhanced detection and provide direct evidence of the non-classical nature of the mechanical oscillator without directly measuring its state. This noninvasive measurement scheme allows to infer information about otherwise inaccessible objects, with potential implications for sensing, open-system dynamics and fundamental tests of quantum gravity. In the future, similar on-chip devices could be used to entangle subsystems on very different energy scales, such as microwave and optical photons.

The field has narrowed in the race to protect sensitive electronic information from the threat of quantum computers, which one day could render many of our current encryption methods obsolete.

As the latest step in its program to develop effective defenses, the National Institute of Standards and Technology (NIST) has winnowed the group of potential encryption tools—known as cryptographic algorithms—down to a bracket of 26. These algorithms are the ones NIST mathematicians and computer scientists consider to be the strongest candidates submitted to its Post-Quantum Cryptography Standardization project, whose goal is to create a set of standards for protecting electronic information from attack by the computers of both tomorrow and today.

“These 26 algorithms are the ones we are considering for potential standardization, and for the next 12 months we are requesting that the cryptography community focus on analyzing their performance,” said NIST mathematician Dustin Moody. “We want to get better data on how they will perform in the real world.”

To work, quantum computers have to be freezing cold, which makes connecting them to one another a challenge.

Now, for the first time, a team of researchers has found a way to create entangled radiation using a physical object — a move that could help connect future quantum computer systems to the outside world.

“What we have built is a prototype for a quantum link,” Shabir Barzanjeh, the engineer who led the project, said in a press release. “The oscillator that we have built has brought us one step closer to a quantum internet.”

The Standard Model is a remarkably successful but incomplete theory. Supersymmetry (SUSY) offers an elegant solution to the Standard Model’s limitations, extending it to give each particle a heavy “superpartner” with different spin properties (an important quantum number distinguishing matter particles from force particles and the Higgs boson). For example, sleptons are the spin 0 superpartners of spin 1/2 electrons, muons and tau leptons, while charginos and neutralinos are the spin 1/2 counterparts of the spin 0 Higgs bosons (SUSY postulates a total of five Higgs bosons) and spin 1 gauge bosons.

If these superpartners exist and are not too massive, they will be produced at CERN’s Large Hadron Collider (LHC) and could be hiding in data collected by the ATLAS detector. However, unlike most processes at the LHC, which are governed by strong force interactions, these superpartners would be created through the much weaker electroweak interaction, thus lowering their production rates. Further, most of these new SUSY particles are expected to be unstable. Physicists can only search for them by tracing their decay products—typically into a known Standard Model particle and the lightest supersymmetric particle (LSP), which could be stable and non-interacting, thus forming a natural dark matter candidate.

On 20 May, 2019, at the Large Hadron Collider Physics (LHCP) conference in Puebla, Mexico, and at the SUSY2019 conference in Corpus Christi, U.S., the ATLAS Collaboration presented numerous new searches for SUSY based on the full LHC Run 2 dataset (taken between 2015 and 2018), including two particularly challenging searches for electroweak SUSY. Both searches target particles that are produced at extremely low rates at the LHC, and decay into Standard Model particles that are themselves difficult to reconstruct. The large amount of data successfully collected by ATLAS in Run 2 provides a unique opportunity to explore these scenarios with new analysis techniques.

One of the essential features required for the realization of a quantum computer is quantum entanglement. A team of physicists from the University of Vienna and the Austrian Academy of Sciences (ÖAW) introduces a novel technique to detect entanglement even in large-scale quantum systems with unprecedented efficiency. This brings scientists one step closer to the implementation of reliable quantum computation. The new results are of direct relevance for future generations of quantum devices and are published in the current issue of the journal Nature Physics.

Quantum computation has been drawing the attention of many scientists because of its potential to outperform the capabilities of standard computers for certain tasks. For the realization of a quantum computer, one of the most essential features is quantum entanglement. This describes an effect in which several quantum particles are interconnected in a complex way. If one of the entangled particles is influenced by an external measurement, the state of the other entangled particle changes as well, no matter how far apart they may be from one another. Many scientists are developing new techniques to verify the presence of this essential quantum feature in quantum systems. Efficient methods have been tested for systems containing only a few qubits, the basic units of quantum information. However, the physical implementation of a quantum computer would involve much larger quantum systems.

Researchers in China are using drones as nodes in the development of an airborne quantum communications network. The article describes how such a network, using a quantum drone would be nigh unhackable.

If we could trap light it could be used as a force field or even a lightsaber in future developments :3.

Quantum computers, which use light particles (photons) instead of electrons to transmit and process data, hold the promise of a new era of research in which the time needed to realize lifesaving drugs and new technologies will be significantly shortened. Photons are promising candidates for quantum computation because they can propagate across long distances without losing information, but when they are stored in matter they become fragile and susceptible to decoherence. Now researchers with the Photonics Initiative at the Advanced Science Research Center (ASRC) at The Graduate Center, CUNY have developed a new protocol for storing and releasing a single photon in an embedded eigenstate—a quantum state that is virtually unaffected by loss and decoherence. The novel protocol, detailed in the current issue of Optica, aims to advance the development of quantum computers.

“The goal is to store and release single photons on demand by simultaneously ensuring the stability of data,” said Andrea Alù, founding director of the ASRC Photonics Initiative and Einstein Professor of Physics at The Graduate Center. “Our work demonstrates that is possible to confine and preserve a single photon in an open cavity and have it remain there until it’s prompted by another photon to continue propagating.”

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Symmetry is a fundamental characteristic in nature. Understanding the mechanisms that break symmetries is essential to scientific research. Spontaneous symmetry breaking (SSB), in particular, occurs when thermal or quantum fluctuations drive a system from a symmetric state into an ordered state, as it occurs when a liquid turns into a solid. This mechanism allows researchers to classify different phases of matter according to the different patterns generated by the broken symmetry.

In the last decades, topology has also been recognized as a crucial characteristic to describe how matter is organized at the fundamental level. In this case, it is no longer the breaking of certain symmetries, but their conservation, which gives rise to novel states of matter, the so-called symmetry-protected topological (SPT) phases. Different topological phases might present the same symmetries, but they can be distinguished by a global topological invariant, which takes integer values and is preserved under continuous deformations.

Current research in condensed matter physics aims to understand how symmetry breaking and symmetry protection compete, in particular in the presence of interactions. In a recent paper published in Nature Communications, ICFO researchers Daniel Gonzalez and Przemyslaw Grzybowski, led by Alexandre Dauphin and ICREA Prof. at ICFO Maciej Lewenstein, in collaboration with Alejandro Bermudez from the Universidad Complutense in Madrid, report how these two processes cooperate, giving rise to new strongly-correlated topological effects.

They’re getting really good, really, really fast.