Novel metamaterial-based architectures offer a promising platform for building mass-producible, reprogrammable schemes that perform computing tasks with light.
Category: computing – Page 181
A new device consisting of a semiconductor ring produces pairs of entangled photons that could be used in a photonic quantum processor.
Quantum light sources produce entangled pairs of photons that can be used in quantum computing and cryptography. A new experiment has demonstrated a quantum light source made from the semiconductor gallium nitride. This material provides a versatile platform for device fabrication, having previously been used for on-chip lasers, detectors, and waveguides. Combined with these other optical components, the new quantum light source opens up the potential to construct a complex quantum circuit, such as a photonic quantum processor, on a single chip.
Quantum optics is a rapidly advancing field, with many experiments using photons to carry quantum information and perform quantum computations. However, for optical systems to compete with other quantum information technologies, quantum-optics devices will need to be shrunk from tabletop size to microchip size. An important step in this transformation is the development of quantum light generation on a semiconductor chip. Several research teams have managed this feat using materials such as gallium aluminum arsenide, indium phosphide, and silicon carbide. And yet a fully integrated photonic circuit will require a range of components in addition to quantum light sources.
Diodes, also known as rectifiers, are a basic component of modern electronics. As we work to create smaller, more powerful and more energy-efficient electronic devices, reducing the size of diodes is a major objective. Recently, a research team from the University of Georgia developed the world’s smallest diode using a single DNA molecule. This diode is so small that it cannot be seen by conventional microscopes.
A diode is an electrical device that allows current to move through it in one direction much more easily than the other. No diode prevents 100% of current flow in one direction while allowing unlimited current in the other direction—in reality, a diode will always allow some current in both the “forward” and “backward” directions. The larger the imbalance favoring the “forward” direction, however, the better diode we have. Diodes are responsible for controlling the current in many common electronic components. Millions of diodes are embedded in a single silicon chip, and to increase the processing power of these chips, the diodes need to be made smaller.
Following a prediction originally made in 1965 by Intel co-founder Gordon Moore, now known as Moore’s law, scientists and engineers have been able to make smaller and smaller computer hardware by doubling the number of electronic components in a silicon chip every 18 months. These improvements in computing power are approaching the physical limits of silicon, however; when silicon components are too small, they will become unstable and their performance unpredictable.
Check out my course about quantum mechanics on Brilliant! First 30 days are free and 20% off the annual premium subscription when you use our link ➜ https://brilliant.org/sabine.
If you flip a light switch, the light will turn on. A cause and its effect. Simple enough… until quantum gravity come into play. Once you add quantum gravity, lights can turn on and make switches flip. And some physicists think that this could help build better computers. Why does quantum physics make causality so strange? And how can we use quantum gravity to build faster computers? Let’s have a look.
The paper on indefinite causal structures is here: https://arxiv.org/abs/quant-ph/0701019
🤓 Check out my new quiz app ➜ http://quizwithit.com/
💌 Support me on Donatebox ➜ https://donorbox.org/swtg.
📝 Transcripts and written news on Substack ➜ https://sciencewtg.substack.com/
👉 Transcript with links to references on Patreon ➜ / sabine.
📩 Free weekly science newsletter ➜ https://sabinehossenfelder.com/newsle…
👂 Audio only podcast ➜ https://open.spotify.com/show/0MkNfXl…
🔗 Join this channel to get access to perks ➜
/ @sabinehossenfelder.
🖼️ On instagram ➜ / sciencewtg.
#science #sciencenews #physics
Very interesting article.
Now a physicist working at the University of Portsmouth in the UK has published research in the AIP Advances journal that he says provides support to the strange theory.
“I don’t want to paraphrase Morpheus from The Matrix but he said ‘what is real?’” the Associate Professor of Physics, Dr Melvin Vopson, said.
“All the senses that we have, they’re just electrical signals that are being decoded by our brains. What this is is a biological computer. There’s nothing more,” he added.
A National Institute for Materials Science (NIMS) research team has developed the world’s first n-channel diamond MOSFET (metal-oxide-semiconductor field-effect transistor). The developed n-channel diamond MOSFET provides a key step toward CMOS (complementary metal-oxide-semiconductor: one of the most popular technologies in the computer chip) integrated circuits for harsh environment applications, as well as the development of diamond power electronics. The research is published in Advanced Science.
Semiconductor diamond has outstanding physical properties such as ultra wide-bandgap energy of 5.5 eV, high carriers mobilities, and high thermal conductivity, which is promising for the applications under extreme environmental conditions with high performance and high reliability, such as the environments with high temperatures and high levels of radiation (e.g., in proximity to nuclear reactor cores).
By using diamond electronics, not only can the thermal management demand for conventional semiconductors be alleviated but these devices are also more energy efficient and can endure much higher breakdown voltages and harsh environments.
When a positive voltage was applied to the chip, the ions flowed to the pore, where their pressure created a blister between the chip’s surface and the graphite layer. When the blister forced the graphite upward, the device became more conductive, switching its memory state to “on.” Since the graphite stayed lifted even without a current, the chip essentially remembered this state, A negative voltage could pull the chip’s layers back together, resetting the device to its “off” state.
The scientists were able to connect two of these chips to form a logic gate —a circuit that can implement logical operations such as AND, OR, and NOT. They note they can build any other classical logic gate commonly employed in digital computing using their logic gate. This is the first time multiple fluidic memristors have been connected to form a circuit.
Previously, scientists developed fluidic memristors based on tiny syringes or microscopic slits. However, these earlier devices were too bulky and complex to scale up to larger systems. In contrast, the new microchips are compact and scalable, Emmerich says.
How Is Flocking Like Computing?
Posted in biological, computing, food, physics
Birds flock. Locusts swarm. Fish school. Within assemblies of organisms that seem as though they could get chaotic, order somehow emerges. The collective behaviors of animals differ in their details from one species to another, but they largely adhere to principles of collective motion that physicists have worked out over centuries. Now, using technologies that only recently became available, researchers have been able to study these patterns of behavior more closely than ever before.
In this episode, the evolutionary ecologist Iain Couzin talks with co-host Steven Strogatz about how and why animals exhibit collective behaviors, flocking as a form of biological computation, and some of the hidden fitness advantages of living as part of a self-organized group rather than as an individual. They also discuss how an improved understanding of swarming pests such as locusts could help to protect global food security.
Listen on Apple Podcasts, Spotify, Google Podcasts, TuneIn or your favorite podcasting app, or you can stream it from Quanta.
The Computational Universe
Posted in computing, quantum physics
Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos. Seth Lloyd. xii + 221 pp. Alfred A. Knopf, 2006. $25.95.
In the 1940s, computer pioneer Konrad Zuse began to speculate that the universe might be nothing but a giant computer continually executing formal rules to compute its own evolution. He published the first paper on this radical idea in 1967, and since then it has provoked an ever-increasing response from popular culture (the film The Matrix, for example, owes a great deal to Zuse’s theories) and hard science alike.
Ever wonder where all the active supermassive black holes are in the universe? Now, with the largest quasar catalog yet, you can see the locations of 1.3 million quasars in 3D.
The catalog, Quaia, can be accessed here.
“This quasar catalog is a great example of how productive astronomical projects are,” says David Hogg, study co-author and computational astrophysicist at the Flatiron Institute, in a press release. “Gaia was designed to measure stars in our galaxy, but it also found millions of quasars at the same time, which give us a map of the entire universe.” By mapping and seeing where quasars are across the universe, astrophysicists can learn more about how the universe evolved, insights into how supermassive black holes grow, and even how dark matter clumps together around galaxies. Researchers published the study this week in The Astrophysical Journal.