Understanding insulators with conducting edges

16.01. 2019 Quantum Physics News

Insulators that are conducting at their edges hold promise for interesting technological applications. However, until now their characteristics have not been fully understood. Physicists at Goethe University have now modelled what are known as topological insulators with the help of ultracold quantum gases. In the current issue of Physical Review Letters, they demonstrate how the edge states could be experimentally detected.

New quantum structures in super-chilled helium may mirror early days of universe

16.01. 2019 Quantum Physics News

For the first time, researchers have documented the long-predicted occurrence of 'walls bound by strings' in superfluid helium-3. The existence of such an object, originally foreseen by cosmology theorists, may help explaining how the universe cooled down after the Big Bang. With the newfound ability to recreate these structures in the lab, earth-based scientists finally have a way to study some of the possible scenarios that might have taken place in the early universe more closely.

Experiments detect entropy production in mesoscopic quantum systems

16.01. 2019 Quantum Physics News

The production of entropy, which means increasing the degree of disorder in a system, is an inexorable tendency in the macroscopic world owing to the second law of thermodynamics. This makes the processes described by classical physics irreversible and, by extension, imposes a direction on the flow of time. However, the tendency does not necessarily apply in the microscopic world, which is governed by quantum mechanics. The laws of quantum physics are reversible in time, so in the microscopic world, there is no preferential direction to the flow of phenomena.

Reimagining information processing

09.01. 2019 Quantum Physics News

Because technology is a part of our everyday lives, it may be difficult to imagine what the future of technology will look like, let alone what it has the potential of accomplishing.

Quantum scientists demonstrate world-first 3-D atomic-scale quantum chip architecture

07.01. 2019 Quantum Physics News

UNSW researchers at the Centre of Excellence for Quantum Computation and Communication Technology (CQC2T) have shown for the first time that they can build atomic precision qubits in a 3-D device—another major step towards a universal quantum computer.

Quantum chemistry on quantum computers

02.01. 2019 Quantum Physics News

Quantum computing and quantum information processing technology have attracted attention in recently emerging fields. Among many important and fundamental issues in science, solving the Schroedinger equation (SE) of atoms and molecules is one of the ultimate goals in chemistry, physics and their related fields. SE is the first principle of non-relativistic quantum mechanics, whose solutions, termed wave functions, can afford any information of electrons within atoms and molecules, predicting their physicochemical properties and chemical reactions.

Machine learning and quantum mechanics team up to understand water at the atomic level

02.01. 2019 Quantum Physics News

Why is water densest at around 4 degrees Celsius? Why does ice float? Why does heavy water have a different melting point compared to normal water? Why do snowflakes have a six-fold symmetry? A collaborative study, led by researchers in EPFL and just published in the Proceedings of the National Academy of Sciences, provides physical insights into these questions by marrying data-driven machine learning techniques and quantum mechanics.

Hybrid qubits solve key hurdle to quantum computing

28.12. 2018 Quantum Physics News

Spin-based quantum computers have the potential to tackle difficult mathematical problems that cannot be solved using ordinary computers, but many problems remain in making these machines scalable. Now, an international group of researchers led by the RIKEN Center for Emergent Matter Science have crafted a new architecture for quantum computing. By constructing a hybrid device made from two different types of qubit—the fundamental computing element of quantum computers—they have created a device that can be quickly initialized and read out, and that simultaneously maintains high control fidelity.

Quantum tricks to unveil the secrets of topological materials

21.12. 2018 Quantum Physics News

Electrons are not just little spheres, bouncing through a material like a rubber ball. The laws of quantum physics tell us that electrons behave like waves. In some materials, these electron waves can take on rather complicated shapes. The so-called "topological materials" produce electron states that can be very interesting for technical applications, but it is extremely difficult to identify these materials and their associated electronic states.

Strong interactions produce a dance between light and sound

21.12. 2018 Quantum Physics News

Light and high-frequency acoustic sound waves in a tiny glass structure can strongly couple to one another and perform a dance in step.

Cold atoms offer a glimpse of flat physics

21.12. 2018 Quantum Physics News

These days, movies and video games render increasingly realistic 3-D images on 2-D screens, giving viewers the illusion of gazing into another world. For many physicists, though, keeping things flat is far more interesting.

David vs. Goliath: What a tiny electron can tell us about the structure of the universe

21.12. 2018 Quantum Physics News

What is the shape of an electron? If you recall pictures from your high school science books, the answer seems quite clear: an electron is a small ball of negative charge that is smaller than an atom. This, however, is quite far from the truth.

The coolest experiment in the universe

21.12. 2018 Quantum Physics News

What's the coldest place you can think of? Temperatures on a winter day in Antarctica dip as low as -120ºF (-85ºC). On the dark side of the Moon, they hit -280ºF (-173ºC). But inside NASA's Cold Atom Laboratory on the International Space Station, scientists are creating something even colder.

Quantum Maxwell’s demon ‘teleports’ entropy out of a qubit

20.12. 2018 Quantum Physics News

Researchers from the Moscow Institute of Physics and Technology, ETH Zurich, and Argonne National Laboratory, U.S, have described an extended quantum Maxwell's demon, a device locally violating the second law of thermodynamics in a system located one to five meters away from the demon. The device could find applications in quantum computers and microscopic refrigerators that cool down tiny objects with pinpoint accuracy. The research was published Dec. 4 in Physical Review B.

Satellite study proves global quantum communication will be possible

20.12. 2018 Quantum Physics News

Researchers in Italy have demonstrated the feasibility of quantum communications between high-orbiting global navigation satellites and a ground station, with an exchange at the single photon level over a distance of 20,000km.