Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Researchers nearly reached quantum limit with nanodrums

31.10.2016

Extremely accurate measurements of microwave signals can potentially be used for data encryption based on quantum cryptography and other purposes.

Researchers at Aalto University and the University of Jyväskylä have developed a new method of measuring microwave signals extremely accurately. This method can be used for processing quantum information, for example by efficiently transforming signals from microwave circuits to the optical regime.


Micro drums enable a nearly noiseless measurement of radio signals. The drum is made of thin superconducting aluminium film on top of a quartz chip (blue background). Image by Mika Sillanpää

Important quantum limit

If you are trying to tune in a radio station but the tower is too far away, the signal gets distorted by noise. The noise results mostly from having to amplify the information carried by the signal in order to transfer it into an audible form. According to the laws of quantum mechanics, all amplifiers add noise. In the early 1980s, US physicist Carlton Caves proved theoretically that the Heisenberg uncertainty principle for such signals requires that at least half an energy quantum of noise must be added to the signal. In everyday life, this kind of noise does not matter, but researchers around the world have aimed to create amplifiers that would come close to Caves’ limit.

‘The quantum limit of amplifiers is essential for measuring delicate quantum signals, such as those generated in quantum computing or quantum mechanical measuring, because the added noise limits the size of signals that can be measured’, explains Professor Mika Sillanpää.

From quantum bits to flying qubits

So far, the solution for getting closest to the limit is an amplifier based on superconducting tunnel junctions developed in the 1980s, but this technology has its problems. Led by Sillanpää, the researchers from Aalto and the University of Jyväskylä combined a nanomechanical resonator – a vibrating nanodrum – with two superconducting circuits, i.e. cavities.

‘As a result, we have made the most accurate microwave measurement with nanodrums so far’, explains Caspar Ockeloen-Korppi from Aalto University, who conducted the actual measurement.

In addition to the microwave measurement, this device enables transforming quantum information from one frequency to another while simultaneously amplifying it.

‘This would for example allow transferring information from superconducting quantum bits to the “flying qubits” in the visible light range and back’, envision the creators of the theory for the device, Tero Heikkilä, Professor at the University of Jyväskylä, and Academy Research Fellow Francesco Massel. Therefore, the method has potential for data encryption based on quantum mechanics, i.e. quantum cryptography, as well as other applications.

The research team also included researchers Juha-Matti Pirkkalainen and Erno Darmskägg from Aalto University. The work was published in Physical Review X, one of the most distinguished journals in physics, 28 October 2016. The work was conducted in the Center of Excellence on Low Temperature Quantum Phenomena and Devices in the Academy of Finland, and it was partially funded by the European Research Council.

http://www.aalto.fi/en/current/news/2016-10-12-007/

  • Full bibliographic informationLow-Noise Amplification and Frequency Conversion with a Multiport Microwave Optomechanical Device; C. F. Ockeloen-Korppi, E. Damskägg, J.-M. Pirkkalainen, T. T. Heikkilä, F. Massel, and M. A. Sillanpää; Phys. Rev. X 6, 041024 – Published 28 October 2016; DOI: https://doi.org/10.1103/PhysRevX.6.041024

For further information, please contact:

Johanna Lassy

+358-50-590 7207

johanna.lassy@aalto.fi

Johanna Lassy | AlphaGalileo

More articles from Physics and Astronomy:

nachricht Magnetic nano-imaging on a table top
20.04.2018 | Georg-August-Universität Göttingen

nachricht New record on squeezing light to one atom: Atomic Lego guides light below one nanometer
20.04.2018 | ICFO-The Institute of Photonic Sciences

All articles from Physics and Astronomy >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Spider silk key to new bone-fixing composite

University of Connecticut researchers have created a biodegradable composite made of silk fibers that can be used to repair broken load-bearing bones without the complications sometimes presented by other materials.

Repairing major load-bearing bones such as those in the leg can be a long and uncomfortable process.

Im Focus: Writing and deleting magnets with lasers

Study published in the journal ACS Applied Materials & Interfaces is the outcome of an international effort that included teams from Dresden and Berlin in Germany, and the US.

Scientists at the Helmholtz-Zentrum Dresden-Rossendorf (HZDR) together with colleagues from the Helmholtz-Zentrum Berlin (HZB) and the University of Virginia...

Im Focus: Gamma-ray flashes from plasma filaments

Novel highly efficient and brilliant gamma-ray source: Based on model calculations, physicists of the Max PIanck Institute for Nuclear Physics in Heidelberg propose a novel method for an efficient high-brilliance gamma-ray source. A giant collimated gamma-ray pulse is generated from the interaction of a dense ultra-relativistic electron beam with a thin solid conductor. Energetic gamma-rays are copiously produced as the electron beam splits into filaments while propagating across the conductor. The resulting gamma-ray energy and flux enable novel experiments in nuclear and fundamental physics.

The typical wavelength of light interacting with an object of the microcosm scales with the size of this object. For atoms, this ranges from visible light to...

Im Focus: Basel researchers succeed in cultivating cartilage from stem cells

Stable joint cartilage can be produced from adult stem cells originating from bone marrow. This is made possible by inducing specific molecular processes occurring during embryonic cartilage formation, as researchers from the University and University Hospital of Basel report in the scientific journal PNAS.

Certain mesenchymal stem/stromal cells from the bone marrow of adults are considered extremely promising for skeletal tissue regeneration. These adult stem...

Im Focus: Like a wedge in a hinge

Researchers lay groundwork to tailor drugs for new targets in cancer therapy

In the fight against cancer, scientists are developing new drugs to hit tumor cells at so far unused weak points. Such a “sore spot” is the protein complex...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

Invitation to the upcoming "Current Topics in Bioinformatics: Big Data in Genomics and Medicine"

13.04.2018 | Event News

Unique scope of UV LED technologies and applications presented in Berlin: ICULTA-2018

12.04.2018 | Event News

IWOLIA: A conference bringing together German Industrie 4.0 and French Industrie du Futur

09.04.2018 | Event News

 
Latest News

Magnetic nano-imaging on a table top

20.04.2018 | Physics and Astronomy

Start of work for the world's largest electric truck

20.04.2018 | Interdisciplinary Research

Atoms may hum a tune from grand cosmic symphony

20.04.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>