Toggle light / dark theme

Get the latest international news and world events from around the world.

Log in for authorized contributors

How pointing errors impact quantum key distribution systems

Quantum key distribution (QKD) is an emerging communication technology that utilizes quantum mechanics principles to ensure highly secure communication between two parties. It enables the sender and receiver to generate a shared secret key over a channel that may be monitored by an attacker. Any attempt to eavesdrop introduces detectable errors in the quantum signals, allowing communicating parties to detect if communication is compromised via QKD protocols.

Among the various parameters that influence the performance of QKD systems, pointing error, a misalignment between the transmitter and receiver, is one of the most important. Such misalignment can arise from mechanical vibrations, atmospheric turbulence, and/or inaccuracies in the alignment mechanisms.

Despite its importance, very few studies have examined pointing error in a comprehensive manner for QKD optical wireless communication (OWC) systems.

New structural insights reveal how human respiratory chain complexes assemble

A new study shows how one of the cell’s most important energy-producing machines is built. Researchers at Karolinska Institutet have mapped late steps in the formation of the human respirasome, a large protein assembly that drives mitochondrial respiration. Their research is published in the journal Nature Communications.

The respirasome is made up of several protein complexes that work together to transfer electrons and support the production of ATP, the cell’s main energy source. Although scientists have known that these complexes can join to create larger structures, it has remained unclear whether they assemble as finished units or form step by step.

Using high-resolution cryo-electron microscopy, the research team at the Department of Medical Biochemistry and Biophysics captured previously unknown intermediates of the respirasome. Their findings suggest that the final stages of assembly occur while one of the key components, complex IV, is still maturing. This indicates that the respirasome may act as a platform that helps guide the correct order of assembly.

Nanoscopic raft dynamics on cell membranes successfully visualized for first time

A collaborative team of four professors and several graduate students from the Departments of Chemistry and Biochemical Science and Technology at National Taiwan University, together with the Department of Applied Chemistry at National Chi Nan University, has achieved a long-sought breakthrough.

By combining atomic force microscopy (AFM) with a Hadamard product–based image reconstruction algorithm, the researchers successfully visualized, for the first time, the nanoscopic dynamics of membrane rafts in live cells—making visible what had long remained invisible on the cell membrane.

Membrane rafts are nanometer-scale structures rich in cholesterol and sphingolipids, believed to serve as vital platforms for cell signaling, viral entry, and cancer metastasis. Since the concept emerged in the 1990s, the existence and behavior of these lipid domains have been intensely debated.

The world’s first room-temperature continuous-wave UV-B laser diode on a sapphire substrate

Ultraviolet-B (UV-B) semiconductor lasers are highly sought for medical, biotechnology, and precision manufacturing applications; however, previous UV-B laser diodes were limited to pulsed operation or required cryogenic cooling, making continuous room-temperature operation unattainable.

Researchers in Japan report the world’s first continuous-wave UV-B semiconductor laser diode operating at room temperature on a low-cost sapphire substrate.

This breakthrough advances compact, energy-efficient UV light sources, potentially replacing bulky gas-based lasers in health care, industrial, and scientific research applications worldwide.

Building the world’s first open-source quantum computer

Researchers from the University of Waterloo’s Faculty of Science and the Institute for Quantum Computing (IQC) are prioritizing collaboration over competition to advance quantum computer development and the field of quantum information. They are doing this through Open Quantum Design (OQD), a non-profit organization that boasts the world’s first open-source, full stack quantum computer.

OQD was co-founded in 2024 by faculty members in the Department of Physics and Astronomy and IQC, Drs. Crystal Senko, Rajibul Islam and Roger Melko, alongside CEO Greg Dick (BSc ‘93).

The group is helping reshape how quantum research is shared, opening doors for the next generation of quantum scientists, and even seeding new quantum startups.

Ultrafast spectroscopy reveals step-by-step energy flow in germanium semiconductors

Whether in a smartphone or laptop, semiconductors form the basis of modern electronics and accompany us constantly in everyday life. The processes taking place inside these materials are the subject of ongoing research. When the electrons in a semiconductor material are activated using light or an electrical voltage, the excited electrons also set the atomic lattice in motion. This results in collective vibrations of the atoms, known as phonons or lattice vibrations, which interact with each other and with the electrons themselves.

These tiny lattice vibrations play a vital role in how energy flows and dissipates through the material—in other words, in how efficiently the energy is redistributed and how strongly the material heats up. Different approaches can be used to control and monitor the propagation of lattice vibrations—and therefore to make the semiconductor more effective and more efficient.

Detailed knowledge of the mechanisms of energy loss and potential overheating is essential in order to design new materials and devices that heat up less, recover faster or respond to external excitation more precisely. A team led by Professor Ilaria Zardo from the University of Basel reports on the unprecedented accuracy they achieved in measurements of energy flow processes within the semiconductor germanium, which is frequently used in computer technology. Their paper is published in Advanced Science.

First direct evidence of Migdal effect opens new path for dark matter search

In a landmark discovery that bridges nearly a century of theoretical physics, a Chinese research team has successfully captured the first direct evidence of the Migdal effect, a breakthrough with profound implications for probing dark matter—the invisible substance thought to make up roughly 85% of the universe.

The finding, published in the journal Nature, confirms a prediction made in 1939 by Soviet physicist Arkady Migdal: When an atomic nucleus suddenly gains energy—for instance, from a collision with a neutral particle (like a neutron or a dark matter candidate)—and recoils, the rapid shift in the atom’s internal electric field can eject one of its orbiting electrons.

For nearly nine decades, this “electron ejection” process remained purely theoretical. Direct evidence proved elusive because the effect occurs on an incredibly tiny scale and is easily masked by background noise from cosmic rays and natural radiation.

Beta-decay half-life measurements reveal evolution of nuclear shell structure

An international team of researchers has systematically measured the β-decay half-lives of 40 nuclei near calcium-54, providing key experimental data for understanding the structure of extremely neutron-rich nuclei.

The study, published in Physical Review Letters, was led by researchers from the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences, in collaboration with institutions including RIKEN in Japan and Peking University.

Atomic nuclei exhibit exceptional stability when the proton (Z) or neutron (N) number reaches certain “magic numbers,” such as 2, 8, 20, 28, 50, 82, or 126. The shell model successfully explained these magic numbers by introducing spin-orbit coupling, a contribution for which M. Mayer and J. Jensen were awarded the Nobel Prize in Physics in 1963.

Observing the positronium beam as a quantum matter wave for the first time

One of the discoveries that fundamentally distinguished the emerging field of quantum physics from classical physics was the observation that matter behaves differently at the smallest scales. A key finding was wave-particle duality, the revelation that particles can exhibit wave-like properties.

This duality was famously demonstrated in the double-slit experiment. When electrons were fired through two slits, they created an interference pattern of light and dark fringes on a detector. This pattern showed that each electron behaved like a wave, with its quantum wave-function passing through both slits and interfering with itself. The same phenomenon was later confirmed for neutrons, helium atoms, and even large molecules, making matter-wave diffraction a cornerstone of quantum mechanics.

Stealth quantum sensors unlock possibilities anywhere GPS doesn’t work

As commercial interest in quantum technologies accelerates, entrepreneurial minds at the University of Waterloo are not waiting for opportunities—they are creating them.

Among them is Alex Maierean (MMath ‘24), CEO of Phantom Photonics and part-time Ph.D. student at the Institute for Quantum Computing (IQC). Her startup is developing ultra-sensitive quantum sensors that can filter out background noise and detect the faintest signals, even down to a single photon—the smallest unit of light. This offers new levels of precision and stealth for industries operating in extreme environments, from the depths of the ocean to outer space.

Launched in 2023, the Velocity startup emerged from fundamental research at an IQC lab led by Dr. Thomas Jennewein, IQC affiliate and adjunct faculty in the Department of Physics and Astronomy. Today, the startup is based at Velocity where it has established a dedicated lab space to continue to develop its quantum sensor technology and build its core team.

/* */