Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: quantum physics – Page 7

All-optical modulation in silicon achieved via an electron avalanche process

Over the past decades, engineers have introduced numerous technologies that rely on light and its underlying characteristics. These include photonic and quantum systems that could advance imaging, communication and information processing.

A key challenge that has so far limited the performance of these new technologies is that most materials used to fabricate them have a weak optical nonlinearity. This essentially means that they do not strongly change in response to light of different intensities.

A strong optical linearity is of crucial importance for the development of ultrafast optical switches, devices that can control either light or electrical signals by modulating the properties of a light-based signal (e.g. its intensity or path). Notably, these switches are central components of fiber optics-based communication systems, photonic devices and quantum technologies.

Colloidal quantum dot photodiodes integrated on metasurfaces for compact SWIR sensors

This week, at the IEEE International Electron Devices Meeting (IEDM 2025), imec, a research and innovation hub in advanced semiconductor technologies, successfully demonstrated the integration of colloidal quantum dot photodiodes (QDPDs) on metasurfaces developed on its 300 mm CMOS pilot line. This pioneering approach enables a scalable platform for the development of compact, miniaturized shortwave infrared (SWIR) spectral sensors, setting a new standard for cost-effective and high-resolution spectral imaging solutions.

Short-wave infrared (SWIR) sensors offer unique capabilities. By detecting wavelengths beyond the visible spectrum, they can reveal contrasts and features invisible to the human eye and can therefore see through certain materials such as plastics or fabrics, or challenging conditions like haze and smoke. Conventional SWIR sensors remain, however, expensive, bulky, and challenging to manufacture, restricting their use to niche applications.

Quantum dot (QD) image sensors, a new class of SWIR sensors, offer a promising alternative, combining lower cost with higher resolution. So far, however, they have operated in broadband rather than in spectral mode.

Tiny optical modulator could enable giant future quantum computers

Researchers have made a major advance in quantum computing with a new device that is nearly 100 times smaller than the diameter of a human hair.

Published in the journal Nature Communications, the breakthrough optical phase modulators could help unlock much larger quantum computers by enabling efficient control of lasers required to operate thousands or even millions of qubits—the basic units of quantum information.

Critically, the team of scientists have developed these devices using scalable manufacturing, avoiding complex, custom builds in favor of those used to make the same technology behind processors already found in computers, phones, vehicles, home appliances—virtually everything powered by electricity (even toasters).

Magic moments with John Bell

This was a monumental breakthrough in the philosophy and foundations of quantum mechanics. Bell derived a mathematical inequality that showed if there were any local “hidden variables” (underlying, deterministic factors) explaining the “spooky” correlations in quantum entanglement, those correlations would have to obey certain limits. Experiments inspired by his theorem (starting with Alain Aspect in the early 1980s) have repeatedly shown that these limits are violated, confirming that quantum entanglement is real, non-local, and that nature fundamentally disagrees with Einstein’s idea of “local realism.”

John Bell, with whom I had a fruitful collaboration and warm friendship, is best known for his seminal work on the foundations of quantum physics, but he also made outstanding contributions to particle physics and accelerator physics.

New iron telluride thin film achieves superconductivity for quantum computer chips

If quantum computing is going to become an every-day reality, we need better superconducting thin films, the hardware that enables storage and processing of quantum information. Too often, these thin films have impurities or other defects that make them useless for real quantum computer chips.

Now, Yuki Sato and colleagues at the RIKEN Center for Emergent Matter Science (CEMS) in Japan have discovered a way to make a superconducting thin film from iron telluride, which is surprising because it is not normally superconducting.

The fabrication process reduces distortion in the crystal structure, making it superconducting at very low temperatures, and thus suitable for use in quantum chips. This study was published in Nature Communications.

Quantum machine learning nears practicality as partial error correction reduces hardware demands

Imagine a future where quantum computers supercharge machine learning—training models in seconds, extracting insights from massive datasets and powering next-gen AI. That future might be closer than you think, thanks to a breakthrough from researchers at Australia’s national research agency, CSIRO, and The University of Melbourne.

Until now, one big roadblock stood in the way: errors. Quantum processors are noisy, and quantum machine learning (QML) models need deep circuits with hundreds of gates. Even tiny errors pile up fast, wrecking accuracy. The usual fix—quantum error correction—may work, but it’s expensive. We’re talking millions of qubits just to run one model. That’s way beyond today’s hardware.

So, what’s the game-changer? The team discovered that you don’t need to correct everything.

Theoretical results could lead to faster, more secure quantum technology

University of Iowa researchers have discovered a method to “purify” photons, an advance that could make optical quantum technologies more efficient and more secure.

The work is published in the journal Optica Quantum.

The researchers investigated two nagging challenges to creating a steady stream of single photons, the gold standard method for realizing photonic quantum computers and secure communication networks. One obstacle is called laser scatter, which occurs when a laser beam is directed at an atom, causing it to emit a photon, which is a single unit of light. While effective, the technique can yield extra, redundant photons, which hampers the optical circuit’s efficiency, much like a wayward current in an electrical circuit.

Quantum clues to consciousness: New research suggests the brain may harness the zero-point field

What if your conscious experiences were not just the chatter of neurons, but were connected to the hum of the universe? In a paper published in Frontiers in Human Neuroscience, I present new evidence indicating that conscious states may arise from the brain’s capacity to resonate with the quantum vacuum—the zero-point field that permeates all of space.

More specifically, I argue that macroscopic quantum effects are at play inside our heads. This insight results from a synthesis of brain architectural and neurophysiological findings supplemented with quantitative model calculations. The novel synthesis suggests that the brain’s basic functional building blocks, cortical microcolumns, couple directly to the zero-point field, igniting the complex dynamics characteristic of conscious processes.

/* */