Building quantum supercomputers: Scientists connect two quantum processors using existing fiber optic cables for the first time
Scientists in the U.K. have successfully connected two separate quantum processors, paving the way for a quantum internet and, potentially, quantum supercomputers.
Increasing the number of quantum bits (otherwise known as qubits) in a quantum computer has proven challenging, as quantum computers are "noisy" — they are sensitive to any interference from heat, movement or electromagnetism and fail much more often than bits in classical computing.
The more qubits there are in a quantum computer, the more complex the system becomes and the greater the risk of decoherence — the loss of quantum information — and the resources needed to prevent errors. That's why scientists are focusing on building more reliable qubits before scaling systems up to the millions of qubits needed for a genuinely useful quantum computer.
In a study published Feb. 5 in the journal Nature, scientists proposed working around this scalability problem by connecting separate quantum processors together using existing fiber optic cabling, thereby increasing the number of available qubits.
This is an important step in demonstrating the feasibility of distributed quantum computing (DQC), whereby quantum processors are connected together to perform calculations. DQC would enable multiple quantum processors to work together to solve increasingly complex problems in far less time than it would take classical supercomputers.
The scientists described how they connected two quantum processors – called Alice and Bob (not to be confused with the quantum computing company Alice & Bob) using a photonic network interface (optical fibers). Sending quantum algorithms across the photonic network interface allowed the two quantum processors to share resources and operate as a single entity.
By connecting the two processors like this, the scientists could also transmit photons, together with quantum information and, for the first time, a quantum algorithm. Such algorithms are the computational functions that enable quantum computers to solve problems. These were shared by exploiting the phenomenon of quantum entanglement between photons.
The quantum processors could also work together on the test problem using the Grover search algorithm — a quantum algorithm that is designed to find a 'needle in a haystack'; searching for a certain piece of information in a large pool of unsorted data.
This breakthrough is key to cracking the scalability problem in quantum computing. Instead of a single machine containing millions of qubits, which would be massive and unwieldy, the new technique allows for computations distributed across many smaller processors. Using small modules of trapped-ion qubits linked by optical cables, it allows qubits in separate QPUs to be entangled.
An additional benefit of connecting processors in a DQC system is ease of maintenance, as modules can be upgraded or replaced without disrupting the rest of the system.
As there was only a 6.6 feet (2 meters) gap between the two quantum processing units (QPUs), future trials of this technology would need to expand the operating distance to ensure the connection remains stable over much longer distances. Quantum repeaters, which increase the range over which quantum information can be transmitted, may also be incorporated into future systems.
Adding more quantum processors would provide further proof that DQC would be a viable solution for building quantum supercomputers. In much the same way that today's supercomputers are hundreds of classical processors connected together, it is theoretically possible to create a quantum supercomputer by linking quantum processors together over vast distances.
RELATED STORIES
—History of quantum computing: 12 key moments that shaped the future of computers
—Quantum computers are here — but why do we need them and what will they be used for?
—World's 'best-performing' quantum computing chip could be used in machines by 2027, scientists claim
As a proof of concept, the experiment proved that DQC is viable. It also creates the foundations for a secure quantum internet, which could allow for a more secure method of transmitting information, as quantum processors in different locations could be used to build a secure communications network.
In a statement, David Lucas, the principal investigator of the research team and lead scientist for the UK Quantum Computing and Simulation Hub, said the team's "experiment demonstrates that network-distributed quantum information processing is feasible with current technology."
However, Lucas admitted there's plenty of work to be done before quantum computers are available for practical applications.
"Scaling up quantum computers remains a formidable technical challenge that will likely require new physics insights as well as intensive engineering effort over the coming years," he said.

Try Our AI Features
Explore what Daily8 AI can do for you:
Comments
No comments yet...
Related Articles
Yahoo
3 hours ago
- Yahoo
Would you board a spacecraft that takes 400 years to reach Alpha Centauri?
When you buy through links on our articles, Future and its syndication partners may earn a commission. Imagine leaving Earth forever and boarding a spaceship designed to carry you and thousands of others on a one-way trip to the nearest star system, Alpha Centauri — a journey that could take 400 years. This is the bold vision behind Chrysalis, a hypothetical spacecraft that could transport 2,400 people over 25 trillion miles (40 trillion kilometers) to the exoplanet Proxima Centauri b. The project won first place in the Project Hyperion Design Competition on July 23, a contest among engineers to design a hypothetical multigenerational spacecraft built for long-duration interstellar travel and capable of sustaining a closed society over centuries. Although this plan is purely hypothetical, it leaves a pressing question for us all: Would you be willing to join this extraordinary journey? Take our poll and let us know what you think in the comments below. Related stories —'The most significant JWST finding to date': James Webb spots — then loses — a giant planet orbiting in the habitable zone of our closest sun-like star —Cosmic rays could help support alien life on worlds outside the 'Goldilocks zone' —The final 'planet parade' of 2025 rises Sunday. Here's how to see the full 6-planet show. Solve the daily Crossword
Yahoo
3 hours ago
- Yahoo
Violent supernova spilled a star's ‘guts' before exploding
A completely new supernova variant finally shows a glimpse of a star's innermost 'guts' moments before its destruction. Detailed in a study published August 20 in the journal Nature, their study confirms a longstanding theory about the internal structure of massive stellar objects, and kicks off a host of new questions. Diving into star innards Astronomers have long posited that a star's innards aren't simply a chaotic, roiling ocean of superheated plasma. Instead, they believe they possess layers of chaotic, roiling superheated plasma. In massive stars (those 10 to 100 times larger than the sun) nuclear fusion forces lighter elements in a stellar core to combine into heavier relatives. Over eons, these increasingly dense elements burn away within the core as lighter elements incinerate across successive, encompassing layers. This ultimately results in an incomprehensibly heavy iron core that, once collapsed, initiates a supernova or black hole event. Previously, researchers have documented examples of stripped stars that already lost their helium, exposing stratified, elemental encasements of helium, carbon, and even oxygen. This is usually where such glimpses always ended–until the discovery of SN2021yfj. 'Something very violent must have happened' In 2021, a team led by astrophysicists at Northwestern University utilized the wide-field camera array at the Zwicky Transient Facility (ZTF) near San Diego to scour the evening skies. ZTF's equipment is particularly designed to spot bright, short-lived events like supernovae. In September 2021, researchers noticed just such an occurrence roughly 2.2 billion light-years away. After some assistance from a collaborator at the W.M. Keck Observatory in Hawai'i, they then proceeded to conduct a spectrographic analysis of their supernova discovery, SN2021yfj.'Almost instantly, we realized it was something we had never seen before, so we needed to study it with all available resources,' study co-author and Northwestern University astrophysicist Steve Schulze said in a statement. Schulze and colleagues didn't find the elements they expected (helium, carbon, nitrogen, or oxygen). Instead, their spectrum analysis displayed huge amounts of silicon, sulfur, and argon. These are all heavier elements produced during stellar nuclear fusion near the end of a star's lifespan. 'This star lost most of the material that it produced throughout its lifetime,' explained Schulze. 'So, we could only see the material formed during the months right before its explosion. Something very violent must have happened to cause that.' 'Exotic pathways' to a star's demise That violent something is still a mystery, although researchers have a theory. This gigantic star had literally ripped itself apart from the inside, revealing a cosmic body 'stripped to the bone,' according to Schulze. The team believes that as the core condensed under its own gravitational strength, it became an even denser inferno. At a certain point, it became so hot and dense that it actually reignited a nuclear fusion process so powerful that it generated a huge energy burst. This, in turn, flung away the star's outer layers. Each subsequent 'pair-instability episode' then shed additional elemental layers. 'One of the most recent shell ejections collided with a pre-existing shell, which produced the brilliant emission that we saw as SN2021yfj,' Schulze theorized. However, he stopped short of saying this was the star's definitive cause-of-death. Other possibilities include a pre-supernova eruption, especially strong stellar winds, or even a run-in with an unknown companion star. 'I wouldn't bet my life that it's correct, because we still only have one discovered example,' said Schulze. 'This star really underscores the need to uncover more of these rare supernovae to better understand their nature and how they form.' But according to study co-author Adam Miller, the discovery doesn't mean he and other astrophysicists need to forget everything they know about star life cycles. 'It's not that our textbooks are incorrect, but they clearly do not fully capture everything produced in nature,' he said. 'There must be more exotic pathways for a massive star to end its life that we [haven't] considered.'


Business Wire
5 hours ago
- Business Wire
Circle Pharma Announces Publication in Nature Demonstrating Robust Pre-clinical Anti-tumor Activity of Cyclin A/B RxL Inhibition
SOUTH SAN FRANCISCO, Calif.--(BUSINESS WIRE)--Circle Pharma, Inc., a clinical-stage biopharmaceutical company pioneering next-generation targeted macrocycle therapeutics for difficult-to-treat cancers, today announced a Nature publication describing robust pre-clinical tumor suppression and novel mechanistic insights from inhibiting the binding of certain protein substrates (that bind via RxL motifs) to cyclins A and B in E2F-high tumor cells. Circle Pharma's oral cyclin A/B RxL inhibitor, CID-078, is a first-in-class, orally bioavailable macrocycle with dual cyclin A and B RxL inhibitory activity that is being evaluated in a Phase 1 clinical trial for patients with advanced solid tumors. Cyclins (including cyclins A and B) are a family of proteins that function as master regulators of the cell cycle by binding to and activating their catalytic partners, the cyclin-dependent kinases (CDKs). Cancers driven by high E2F activity, such as small cell lung cancer (SCLC) and other tumors with RB1 alterations, have an overactive cell cycle that leads to uncontrolled tumor cell proliferation. In preclinical models, cyclin A/B RxL inhibitors: Blocked the cyclin A-E2F interaction, triggering aberrant sustained E2F activity, DNA damage, and replication stress. Subsequently disrupted the cyclin B-Myt1 interaction, removing a critical safety brake and forcing damaged tumor cells through division, causing tumor cell death. Produced robust anti-tumor activity, including in chemotherapy-resistant SCLC patient-derived xenograft models. The publication, which was co-authored by scientists from Circle Pharma and the Dana-Farber Cancer Institute, Harvard Medical School, the University of Texas Southwestern Medical Center, and the University of Oxford, can be accessed here (doi: 10.1038/s41586-025-09433-w). 'We are excited to have the novel biology and compelling anti-cancer effects of the cyclin A/B RxL inhibitors developed at Circle recognized within the broader scientific community through this publication in Nature,' said David J. Earp, J.D., Ph.D., president and chief executive officer of Circle Pharma. 'This work underscores the capabilities of our MXMO™ platform to generate oral, cell-permeable macrocycle therapies, such as CID-078, including for historically undruggable targets such as cyclins. With our first-in-human Phase 1 study of CID-078 well underway, we are eager to see the innovative research outlined in this publication translate into new, high-impact therapeutic options for people living with cancer.' 'These findings build upon previous work and reveal additional gain-of-function mechanisms through which cyclin A/B RxL inhibition triggers apoptosis in cancer cells, further supporting this approach for E2F-driven cancers, such as cancers with RB1 alterations, which includes nearly all SCLCs, up to half of triple-negative breast cancers, and subsets of other solid tumors,' said Matthew G. Oser, M.D., Ph.D., senior author of the publication and associate professor of medicine at Dana-Farber Cancer Institute and Harvard Medical School. 'Circle Pharma's cell-permeable, oral macrocycles are designed to overcome the limitations of other therapeutic modalities and are ideally positioned to access cyclins and other historically undruggable targets, offering exciting potential for patients with cancer.' About CID-078, Circle Pharma's Oral Cyclin A/B RxL Inhibitor Program CID-078 is an orally bioavailable macrocycle with dual activity blocking protein-protein interactions between both cyclins A and B and key substrates that bind to them via conserved RxL motifs. CID-078 selectively targets tumor cells with oncogenic alterations that cause cell cycle dysregulation, including alterations in the tumor suppressor RB1. In pre-clinical studies, Circle Pharma's cyclin A/B RxL inhibitors have been shown to potently and selectively disrupt the protein-to-protein interaction between cyclins A and B and their key substrates and modulators, including E2F (a substrate of cyclin A) and MYT1 (a modulator of cyclin B). Preclinical studies have demonstrated the ability of these cyclin A/B RxL inhibitors to cause single-agent tumor regressions in multiple in vivo models. A multi-center Phase 1 clinical trial (NCT06577987) is currently enrolling patients with advanced solid tumors harboring RB1 alterations. About Circle Pharma Circle Pharma is a clinical-stage biopharmaceutical company harnessing the power of macrocycles to develop next-generation targeted therapies for cancer and other serious illnesses. The company's proprietary MXMO™ platform overcomes key challenges in macrocycle drug development, enabling the creation of intrinsically cell-permeable and orally bioavailable therapies, including for historically undruggable targets. Circle Pharma's pipeline is focused on targeting cyclins, key regulators of the cell cycle that drive many cancers. The company's lead program, CID-078, is a cyclin A/B RxL inhibitor in Phase 1 clinical development for patients with advanced solid tumors. Circle Pharma is based in South San Francisco, CA. For additional information, please visit us at and follow us on LinkedIn and X.