Category: quantum computing

BY MATT SWAYNE

• Qunnect announced the construction of a new fiber loop that expands its quantum networking testbed, GothamQ, from Brooklyn to Manhattan.
• The loop, which will connect New York University to the Navy Yard, is another step toward unlocking quantum internet capabilities for customers in financial services, critical infrastructure, and telecom in the New York metropolitan area, the company reports.
• Critical Quote: “We are building a creative collaboration whereby the educational and research environment can be used to develop a better understanding of quantum communication networks.” — Javad Shabani, NYU Arts & Science physicist.
• Image: Entangling New York City: In partnership with New York University (NYU), Qunnect has begun experiments to prove the feasibility of distribution of commercially-usable entanglement on some of the world’s noisiest, traffic-heavy fiber networks. Source: Qunnect.

PRESS RELEASE — – Qunnect, an industry leader in quantum-secure networking technology designed for scalable deployment on existing telecom fiber infrastructure, announced the construction of a new fiber loop that expands its quantum networking testbed, GothamQ, from Brooklyn to Manhattan. Connecting New York University (NYU) to the Navy Yard, Qunnect is poised to unlock quantum internet capabilities for customers in financial services, critical infrastructure, and telecom in the New York metropolitan area.

Researchers were able to send a signal through the open wormhole, though it’s not clear in what sense the wormhole can be said to exist.Credit: Kim Taylor/Quanta Magazine

Physicists have purportedly created the first-ever wormhole, a kind of tunnel theorized in 1935 by Albert Einstein and Nathan Rosen that leads from one place to another by passing into an extra dimension of space.

The wormhole emerged like a hologram out of quantum bits of information, or “qubits,” stored in tiny superconducting circuits. By manipulating the qubits, the physicists then sent information through the wormhole, they reported today in the journal Nature.

Artistic impression of a unimon qubit in a quantum processor.

A group of scientists from Aalto University, IQM Quantum Computers, and VTT Technical Research Center have discovered a new superconducting qubit, the unimon, to increase the accuracy of quantum computations. The team has achieved the first quantum logic gates with unimons at 99.9% fidelity—a major milestone on the quest to build commercially useful quantum computers. This research was just published in the journal Nature Communications.

Of all the different approaches to build useful quantum computers, superconducting qubits are in the lead. However, the qubit designs and techniques currently used do not yet provide high enough performance for practical applications. In this noisy intermediate-scale quantum (NISQ) era, the complexity of the implementable quantum computations is mostly limited by errors in single- and two-qubit quantum gates. The quantum computations need to become more accurate to be useful. 

“Our aim is to build quantum computers which deliver an advantage in solving real-world problems. Our announcement today is an important milestone for IQM, and a significant achievement to build better superconducting quantum computers,” said Professor Mikko Möttönen, joint Professor of Quantum Technology at Aalto University and VTT, and also a Co-Founder and Chief Scientist at IQM Quantum Computers, who was leading the research.

File illustration of the Chinese satellite Micius.

A Chinese micro-nano quantum satellite has entered its planned orbit and is now operational, the University of Science and Technology of China (USTC), one of its developers, said on Thursday.

The low-orbit satellite was designed to conduct real-time quantum key distribution experiments between the satellite and ground station, and to carry out technical verification. It was launched atop a Lijian-1 carrier rocket from the Jiuquan Satellite Launch Center in northwest China on Wednesday.

The new micro-nano satellite’s weight is about one-sixth the weight of the world’s first quantum satellite, the Chinese satellite Micius, which weighs more than 600 kilograms, according to the USTC.

The university said that, based on the quantum technology first seen in Micius, it is clear that more low-cost quantum satellites are needed to realize an efficient, practical and global quantum communication network that can meet the increasing user demand.

By Andrew Griffin

Scientists have made a quantum computer that breaks free from the binary system.

Computers as we know them today rely on binary information: they operate in ones and zeroes, storing more complex information in “bits” that are either off or on. That seemingly simple system is at the heart of every computer we use.

Quantum computers have taken on that same system. They use qubits, which replicate the bits of a classical computer but using quantum technology.

But they are built with more than just those ones and zeroes. Quantum computers are not necessarily restricted to binary, and scientists hope that breaking them are from that system can add extra complexity without using more quantum particles.

Now scientists say they have succeeded in building a quantum computer that works in that way. It can do calculations not with qubits but instead with qudits – quantum digits that could allow for vastly more computing power.

By Sierra Mitchell

Quantum cryptography promises a future in which computers communicate with one another over ultrasecure links using the razzle-dazzle of quantum physics. But scaling up the breakthroughs in research labs to networks with a large number of nodes has proved difficult. Now an international team of researchers has built a scalable city-wide quantum network to share keys for encrypting messages.

The network can grow in size without incurring an unreasonable escalation in the costs of expensive quantum hardware. Also, this system does not require any node to be trustworthy, thus removing any security-sapping weak links.

“We have tested it both in the laboratory and in deployed fibers across the city of Bristol” in England, says Siddarth Koduru Joshi of the University of Bristol. He and his colleagues demonstrated their ideas using a quantum network with eight nodes in which the most distant nodes were 17 kilometers apart, as measured by the length of the optical fiber connecting them. The team’s findings appeared in Science Advances on September 2.

BY MATT SWAYNE

UNIVERSITY RESEARCH NEWS — Researchers at the Simon Fraser University report on research, published in Nature today, that they say could pave the way toward an all-silicon quantum internet and quantum computers that can tackle real-world computational challenges. That internet theoretically will be much more secure and much more powerful than today’s version.

In the study, the scientists describe their observations of silicon ‘T centre’ photon-spin qubits, an important milestone that unlocks immediate opportunities to construct massively scalable quantum computers and the quantum internet that will connect them.

Quantum computing has enormous potential to provide computing power well beyond the capabilities of today’s supercomputers, which could enable advances in many other fields, including chemistry, materials science, medicine and cybersecurity. In order to make this a reality, it is necessary to produce both stable, long-lived qubits that provide processing power, as well as the communications technology that enables these qubits to link together at scale.

Past research has indicated that silicon can produce some of the most stable and long-lived qubits in the industry. Now the research published by Daniel Higginbottom, Alex Kurkjian, and co-authors provides proof of principle that T centres, a specific luminescent defect in silicon, can provide a ‘photonic link’ between qubits.

This comes out of the SFU Silicon Quantum Technology Lab in SFU’s Physics Department, co-led by Stephanie Simmons, Canada Research Chair in Silicon Quantum Technologies and Michael Thewalt, Professor Emeritus.  “This work is the first measurement of single T centres in isolation, and actually, the first measurement of any single spin in silicon to be performed with only optical measurements,” says Stephanie Simmons.