Researchers measure near-perfect performance in low-cost semiconductors

16.03. 2019 Quantum Physics News

Tiny, easy-to-produce particles, called quantum dots, may soon take the place of more expensive single crystal semiconductors in advanced electronics found in solar panels, camera sensors and medical imaging tools. Although quantum dots have begun to break into the consumer market—in the form of quantum dot TVs—they have been hampered by long-standing uncertainties about their quality. Now, a new measurement technique developed by researchers at Stanford University may finally dissolve those doubts.

Speeding up artificial intelligence

15.03. 2019 Quantum Physics News

A group at Politecnico di Milano has developed an electronic circuit able to solve a system of linear equations in a single operation in the timescale of a few tens of nanoseconds. The performance of this new circuit is superior not only to classical digital computers, but also to quantum computers. It will be soon possible to develop a new generation of computing accelerators that will revolutionize the technology of artificial intelligence.

Long-distance quantum information exchange—success at the nanoscale

15.03. 2019 Quantum Physics News

At the Niels Bohr Institute, University of Copenhagen, researchers have realized the swap of electron spins between distant quantum dots. The discovery brings us a step closer to future applications of quantum information, as the tiny dots have to leave enough room on the microchip for delicate control electrodes. The distance between the dots has now become big enough for integration with traditional microelectronics and perhaps, a future quantum computer. The result is achieved via a multinational collaboration with Purdue University and UNSW, Sydney, Australia, now published in Nature Communications.

Researchers put machine learning on path to quantum advantage

14.03. 2019 Quantum Physics News

There are high hopes that quantum computing's tremendous processing power will someday unleash exponential advances in artificial intelligence. AI systems thrive when the machine learning algorithms used to train them are given massive amounts of data to ingest, classify and analyze. The more precisely that data can be classified according to specific characteristics, or features, the better the AI will perform. Quantum computers are expected to play a crucial role in machine learning, including the crucial aspect of accessing more computationally complex feature spaces – the fine-grain aspects of data that could lead to new insights.

Testing the symmetry of space-time by means of atomic clocks

13.03. 2019 Quantum Physics News

In his Special Theory of Relativity, Einstein formulated the hypothesis according to which the speed of light is always the same, no matter what the conditions are. It may, however, be possible that—according to theoretical models of quantum gravitation—this uniformity of space-time does not apply to particles. Physicists have now tested this hypothesis with a first long-term comparison of two optical ytterbium clocks at the Physikalisch-Technische Bundesanstalt (PTB). With these clocks, whose error amounts to only one second in ten billion years, it should be possible to measure even extremely small deviations of the movement of the electrons in ytterbium. But the scientists did not detect any change when the clocks were oriented differently in space. Due to this result, the current limit for testing the space-time symmetry by means of experiments has been drastically improved by a factor of 100. In addition to this, the extremely small systematic measurement uncertainty of the optical ytterbium clocks of less than 4 × 10-18 has been confirmed. The team consisting of physicists from PTB and from the University of Delaware has published its results in the current issue of Nature.

Can artificial intelligence solve the mysteries of quantum physics?

13.03. 2019 Quantum Physics News

Under the direction of Mobileye founder Amnon Shashua, a research group at Hebrew University of Jerusalem's School of Engineering and Computer Science has proven that artificial intelligence (AI) can help us understand the world on an infinitesimally small scale called quantum physics phenomena.

Physicists reverse time using quantum computer

13.03. 2019 Quantum Physics News

Researchers from the Moscow Institute of Physics and Technology teamed up with colleagues from the U.S. and Switzerland and returned the state of a quantum computer a fraction of a second into the past. They also calculated the probability that an electron in empty interstellar space will spontaneously travel back into its recent past. The study is published in Scientific Reports.

Quantum physicists succeed in controlling energy losses and shifts

11.03. 2019 Quantum Physics News

Quantum computers need to preserve quantum information for a long time to be able to crack important problems faster than a normal computer. Energy losses take the state of the qubit from one to zero, destroying stored quantum information at the same time. Consequently, scientists all over the globe have traditionally worked to remove all sources of energy loss—or dissipation—from these machines.

Opening the path to scaling silicon quantum computers

11.03. 2019 Quantum Physics News

Research collaboration between UNSW and the University of Sydney has overcome a fundamental hurdle to building quantum computers in silicon, opening the way to further develop the machines at scale.

Using quantum measurements to fuel a cooling engine

11.03. 2019 Quantum Physics News

Researchers at the University of Florence and Istituto dei Sistemi Complessi, in Italy, have recently proved that the invasiveness of quantum measurements might not always be detrimental. In a study published in Physical Review Letters, they showed that this invasive quality can actually be exploited, using quantum measurements to fuel a cooling engine.

Listening to quantum radio

08.03. 2019 Quantum Physics News

Researchers at Delft University of Technology have created a quantum circuit to listen to the weakest radio signal allowed by quantum mechanics. This new quantum circuit opens the door to possible future applications in areas such as radio astronomy and medicine (MRI). It also enables experiments to shed light on the interplay between quantum mechanics and gravity. The results have been published in Science.

Can entangled qubits be used to probe black holes? (Update)

06.03. 2019 Quantum Physics News

Physicists have used a seven-qubit quantum computer to simulate the scrambling of information inside a black hole, heralding a future in which entangled quantum bits might be used to probe the mysterious interiors of these bizarre objects.

A study researches the limits of topological insulators using sound waves

06.03. 2019 Quantum Physics News

In these kinds of structures, sound signals remain robust and insensitive to noise caused by impurities and defects in the material. In the framework of this research, scientists have discovered that the acoustic topological insulator could act as an extremely robust waveguide, capable of radiating sound in a very narrow ray towards the far field. This focused acoustic ray could be extremely important for applications such as non-destructive testing by ultrasound or in diagnostic ultrasound scans in medicine and biology, as pointed out by the researchers.

IBM announces that its System Q One quantum computer has reached its ‘highest quantum volume to date’

05.03. 2019 Quantum Physics News

IBM has announced at this year's American Physical Society meeting that its System Q One quantum computer has reached its "highest quantum volume to date"—a measure that the computer has doubled in performance in each of the past two years, the company reports.

Ultracold atoms could provide 2-D window to exotic 1-D physics

04.03. 2019 Quantum Physics News

Rice University physicists Matthew Foster and Seth Davis want to view a vexing quantum puzzle from an entirely new perspective. They just need the right vantage point and a place colder than deep space.