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Primeur weekly 2018-03-26

Quantum computing

Physicists reveal material for high-speed quantum internet ...

Focus on Europe

TUM junior scientist wins prestigious award for Computational Studies of Surface Catalytic Processes ...

Cosmologists create largest simulation of galaxy formation and break their own record ...

GigaSpaces triples annual revenue in France, building on strong global 2017 results ...

Atos and GENCI launch the Atos Joseph Fourier Award 2018 to accelerate research and innovation in numerical simulation, artificial intelligence and quantum computing ...

Middleware

Cavium Collaborates with Microsoft to demonstrate ThunderX2 platform compliant with Microsoft's Project Olympus specifications ...

Hardware

Pioneers of computer architecture receive ACM Turing Award ...

Mellanox's advanced Ethernet solutions selected to connect the Tel-Aviv Stock Exchange network infrastructure ...

GIGABYTE announces ThunderXStation: Industry's first Armv8 workstation based on Cavium's ThunderX2 processor ...

Cavium announces Packet Trakker: A programmable network telemetry suite ...

Applications

Los Alamos releases file index product to software community ...

NERSC supercomputers help researchers create reference catalogue for rumen microbiome ...

Major AI breakthrough by Optalysys demonstrating how its patented Optical Processing Technology performs deep learning at the speed of light ...

NVIDIA RTX technology realizes dream of real-time cinematic rendering ...

Batteries out of thin air ...

New method manages and stores data from millions of nerve cells - in real time ...

Groundbreaking research results in artificial intelligence ...

Taming chaos: Calculating probability in complex systems ...

Physicists made crystal lattice from polaritons ...

Golden touch: Next-gen optical disk to solve data storage challenge ...

COSMIC impact: Next-gen X-ray microscopy platform now operational ...

The Cloud

Mellanox simplifies hybrid Cloud connectivity between enterprises and Microsoft Azure ...

Cavium Technologies power end-to-end NVMe over Fabrics solutions ...

Physicists reveal material for high-speed quantum internet


Electrical excitation causes a point defect in the crystal lattice of silicon carbide to emit single photons, which are of use to quantum cryptography. Credit: Elena Khavina, MIPT Press Office.
21 Mar 2018 Moscow - The race for quantum computing is on: Industry giants, such as Google, IBM, and Microsoft, and leading international research centres and universities are involved in the global effort to build a quantum computer. It is not known yet when this new technology can become a reality, but the world is getting ready. The greatest expectation about the quantum computer is that it could break the security of all classical data transfer networks. Today, sensitive data such as personal communication or financial information are protected using encryption algorithms that would take a classical supercomputer years to crack. A quantum computer could conceivably do this in a few seconds.

Luckily, quantum technologies come with a way of neutralizing this threat. Modern classical cryptographic algorithms are complexity-based and can remain secure only for a certain period of time. Unlike its classical counterpart, quantum cryptography relies on the fundamental laws of physics, which can guarantee security of data transmission forever. The operation principle is based on the fact that one cannot copy an unknown quantum state without altering the original message. This means that a quantum communication line cannot be compromised without the sender and the receiver knowing. Even a quantum computer would be of no use to eavesdroppers.

Photons - the quanta of light - are the best carriers for quantum bits. It is important to emphasize that only single photons can be used, otherwise an eavesdropper might intercept one of the transmitted photons and thus get a copy of the message. The principle of single-photon generation is quite simple: An excited quantum system can relax into the ground state by emitting exactly one photon. From an engineering standpoint, one needs a real-world physical system that reliably generates single photons under ambient conditions. However, such a system is not easy to find. For example, quantum dots could be a good option, but they only work well when cooled below -200 degrees Celsius, while the newly emerged two-dimensional materials, such as graphene, are simply unable to generate single-photons at a high repetition rate under electrical excitation.

The MIPT researchers see the solution in silicon carbide, a semiconductor material long forgotten in opto-electronics. "In 2014, we were studying diamond and turned our attention to silicon carbide almost by accident. We figured it had vast potential", stated Dmitry Fedyanin. However, as he explained, electrically driven emission of single photons in this semiconductor was only achieved one year later, in 2015, by an Australian research team.

Surprisingly, silicon carbide is a material that started the whole of opto-electronics: The phenomenon of electroluminescence, in which an electric current causes a material to emit light, was observed for the first time in silicon carbide. In the 1920s, the material was used in the world's first light-emitting diodes (LEDs). In the '70s, silicon carbide LEDs were mass-produced in the Soviet Union. However, after that, silicon carbide lost the battle against direct-bandgap semiconductors and was abandoned by opto-electronics. Nowadays, this material is mostly known for being extremely hard and heat-resistant - it is used in high-power electronics, bulletproof vests, and the brakes of sports cars produced by Porsche, Lamborghini, and Ferrari.

Together with his colleagues, Dmitry Fedyanin studied the physics of electroluminescence of colour centres in silicon carbide and came up with a theory of single-photon emission upon electrical injection that explains and accurately reproduces the experimental findings. A color center is a point defect in the lattice structure of silicon carbide that can emit or absorb a photon at a wavelength to which the material is transparent in the absence of defects. This process is at the heart of the electrically driven single-photon source.

Using their theory, the researchers have shown how a single-photon emitting diode based on silicon carbide can be improved to emit up to several billion photons per second. That is exactly what one needs to implement quantum cryptography protocols at data transfer rates on the order of 1 Gbps. Study co-authors Igor Khramtsov and Andrey Vyshnevyy pointed out that new materials are likely to be found, rivaling silicon carbide in terms of brightness of single-photon emission. However, unlike silicon carbide, they will require new technological processes to be used in mass production of devices. By contrast, silicon carbide-based single-photon sources are compatible with the CMOS technology, which is a standard for manufacturing electronic integrated circuits. This makes silicon carbide by far the most promising material for building practical ultrawide-bandwidth unconditionally secure data communication lines.

The study was supported by the Russian Science Foundation (17-79-20421).

The original research paper is authored by I.A. Khramtsov, A.A. Vyshnevyy, and D.Yu. Fedyanin. The title is " Enhancing the brightness of electrically driven single-photon sources using color centers in silicon carbide ". The paper is publised innpj Quantum Information4, 15 (2018).

Source: Moscow Institute of Physics and Technology - MIPT

Back to Table of contents

Primeur weekly 2018-03-26

Quantum computing

Physicists reveal material for high-speed quantum internet ...

Focus on Europe

TUM junior scientist wins prestigious award for Computational Studies of Surface Catalytic Processes ...

Cosmologists create largest simulation of galaxy formation and break their own record ...

GigaSpaces triples annual revenue in France, building on strong global 2017 results ...

Atos and GENCI launch the Atos Joseph Fourier Award 2018 to accelerate research and innovation in numerical simulation, artificial intelligence and quantum computing ...

Middleware

Cavium Collaborates with Microsoft to demonstrate ThunderX2 platform compliant with Microsoft's Project Olympus specifications ...

Hardware

Pioneers of computer architecture receive ACM Turing Award ...

Mellanox's advanced Ethernet solutions selected to connect the Tel-Aviv Stock Exchange network infrastructure ...

GIGABYTE announces ThunderXStation: Industry's first Armv8 workstation based on Cavium's ThunderX2 processor ...

Cavium announces Packet Trakker: A programmable network telemetry suite ...

Applications

Los Alamos releases file index product to software community ...

NERSC supercomputers help researchers create reference catalogue for rumen microbiome ...

Major AI breakthrough by Optalysys demonstrating how its patented Optical Processing Technology performs deep learning at the speed of light ...

NVIDIA RTX technology realizes dream of real-time cinematic rendering ...

Batteries out of thin air ...

New method manages and stores data from millions of nerve cells - in real time ...

Groundbreaking research results in artificial intelligence ...

Taming chaos: Calculating probability in complex systems ...

Physicists made crystal lattice from polaritons ...

Golden touch: Next-gen optical disk to solve data storage challenge ...

COSMIC impact: Next-gen X-ray microscopy platform now operational ...

The Cloud

Mellanox simplifies hybrid Cloud connectivity between enterprises and Microsoft Azure ...

Cavium Technologies power end-to-end NVMe over Fabrics solutions ...