Which physical mechanism is responsible for magnetic properties of cuprates upon doping?

16.11. 2018 Quantum Physics News

An international team of researchers has identified and proved that adding impurities with a lower concentration of electrons stabilizes the antiferromagnetic state of cuprates, high-temperature superconducting compounds based on copper. The research team, led by a senior fellow at Ural Federal University, Evgeny Stepanov, has published the results of the study in npj Quantum Materials.

Quantum artificial life created on the cloud

16.11. 2018 Quantum Physics News

A project by the UPV/EHU-University of the Basque Country has for the first time implemented a model of quantum artificial life on a quantum computer.

Quantum science turns social

15.11. 2018 Quantum Physics News

Researchers in a lab at Aarhus University have developed a versatile remote gaming interface that allowed external experts as well as hundreds of citizen scientists all over the world to optimize a quantum gas experiment through multiplayer collaboration and in real time. The efforts of both teams dramatically improved upon the previous best solutions established after months of careful experimental optimization. Comparing domain experts, algorithms and citizen scientists is a first step towards unraveling how humans solve complex, natural science problems.

A magnetic method to control the transport of chiral Majorana fermions

13.11. 2018 Quantum Physics News

The Majorana fermion, a particle that is its own antiparticle, was originally introduced as a putative elementary particle by Ettore Majorana in 1937, and the chiral Majorana fermion was experimentally observed in topological superconductors in 2017. Since the Majorana fermion is a charge-neutral particle, the direct effect on Majorana fermions by electromagnetic methods should fail. Now, researchers have proposed a scheme to control the transport of chiral Majorana edge modes in a ring-shaped Josephson junction of a topological superconductor using magnetic flux.

A two-atom quantum duet

09.11. 2018 Quantum Physics News

Researchers at the Center for Quantum Nanoscience (QNS) within the Institute for Basic Science (IBS) achieved a major breakthrough in shielding the quantum properties of single atoms on a surface. The scientists used the magnetism of single atoms, known as spin, as a basic building block for quantum information processing. The researchers could show that by packing two atoms closely together they could protect their fragile quantum properties much better than for just one atom.

Quantum ‘compass’ could allow navigation without relying on satellites

09.11. 2018 Quantum Physics News

The UK's first quantum accelerometer for navigation has been demonstrated by a team from Imperial College London and M Squared.

Sandwich structure of nanocrystals as quantum light source

08.11. 2018 Quantum Physics News

Excited photo-emitters can cooperate and radiate simultaneously, a phenomenon called superfluorescence. Researchers from Empa and ETH Zurich, together with colleagues from IBM Research Zurich, have recently been able to create this effect with long-range ordered nanocrystal superlattices. This discovery could enable future developments in LED lighting, quantum sensing, quantum communication and future quantum computing. The study has just been published in the renowned journal Nature.

Quantum systems: Same, but different

08.11. 2018 Quantum Physics News

Remarkable rules have been detected in the apparent chaos of disequilibrium processes. Different systems behave identically in many ways, if they belong to the same "universality class." This means that experiments can be carried out with quantum systems that are easy to handle in order to obtain precise information about systems that cannot be directly studied in the experiment—such as the Big Bang.

Experiments with optical tweezers race to test the laws of quantum mechanics

07.11. 2018 Quantum Physics News

One might think that the optical tweezer – a focused laser beam that can trap small particles – is old hat by now. After all, the tweezer was invented by Arthur Ashkin in 1970. And he received the Nobel Prize for it this year—presumably after its main implications had been realized during the last half-century.

Coping with errors in the quantum age

06.11. 2018 Quantum Physics News

Quantum systems can be manipulated with extremely high precision, but not perfectly. Researchers in the Department of Physics at ETH Zurich have now demonstrated how to monitor and correct errors that occur during such operations.

How to certify a quantum computer

05.11. 2018 Quantum Physics News

Quantum computers are being developed by teams working not only at universities but also at Google, IBM, Microsoft and D-Wave, a start-up company. And things are evolving quickly, says Nicolas Sangouard, SNSF Professor at the University of Basel. "In a few years at most, I expect the computing power of quantum computers to significantly outstrip the computing power of ordinary computers. We call that 'quantum supremacy'".

One step closer to complex quantum teleportation

05.11. 2018 Quantum Physics News

The experimental mastery of complex quantum systems is required for future technologies like quantum computers and quantum encryption. Scientists from the University of Vienna and the Austrian Academy of Sciences have broken new ground. They sought to use more complex quantum systems than two-dimensionally entangled qubits and thus can increase the information capacity with the same number of particles. The developed methods and technologies could in the future enable the teleportation of complex quantum systems. The results of their work, "Experimental Greenberger-Horne-Zeilinger entanglement beyond qubits," is published recently in the renowned journal Nature Photonics.

Quantum predictions

02.11. 2018 Quantum Physics News

Solving a complex problem quickly requires careful tradeoffs – and simulating the behavior of materials is no exception. To get answers that predict molecular workings feasibly, scientists must swap in mathematical approximations that speed computation at accuracy's expense.

Quantum on the edge: Light shines on new pathway for quantum technology

01.11. 2018 Quantum Physics News

Scientists in Australia have for the first time demonstrated the protection of correlated states between paired photons—packets of light energy—using the intriguing physical concept of topology. This experimental breakthrough opens a pathway to build a new type of quantum bit, the building blocks for quantum computers.

Active noise control for a quantum drum

01.11. 2018 Quantum Physics News

Researchers at the Schliesser Lab at the Niels Bohr Institute, University of Copenhagen, have demonstrated a new way to address a central problem in quantum physics: at the quantum scale, any measurement disturbs the measured object. This disturbance limits, for example, the precision with which the motion of an object can be tracked. But in a millimeter-sized membrane that vibrates like a drumhead, the researchers have managed to precisely monitor the motion with a laser—and to undo the quantum disturbance by the measurement. This allows them to control the membrane's motion at the quantum level. The result has potential applications in ultraprecise sensors of position, velocity and force, and the architecture of a future quantum computer. It is now published in the prestigious scientific magazine, Nature.