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Einstein’s light quanta through the lens of Maxwell’s equations

Light was long considered to be a wave, exhibiting the phenomenon of interference in which ripples like those in water waves are generated under specific interactions. Light also bends around corners, resulting in fringing effects, which is termed diffraction. The energy of light is associated with its intensity and is proportional to the square of the amplitude of the electric field, but in the photoelectric effect, the energy of emitted electrons is found to be proportional to the frequency of radiation.

This observation was first made by Philipp Lenard, who did initial work on the photoelectric effect. In order to explain this, in 1905, Einstein suggested in Annalen der Physik that light comprises quantized packets of , which came to be called photons. It led to the theory of the dual nature of light, according to which light can behave like a wave or a particle depending on its interactions, paving the way for the birth of quantum mechanics.

Although Einstein’s work on photons found broader acceptance, eventually leading to his Nobel Prize in Physics, Einstein was not fully convinced. He wrote in a 1951 letter, “All the 50 years of conscious brooding have brought me no closer to the answer to the question: What are light quanta?”

Physicists achieve record-breaking electron beam power and current

A team of physicists at the SLAC National Accelerator Laboratory, in Menlo Park, California, generated the highest-current, highest-peak-power electron beams ever produced. The team has published their paper in Physical Review Letters.

For many years, scientists have been finding new uses for high-powered laser light, from splitting atoms to mimicking conditions inside other planets. For this new study, the research team upped the power of electron beams, giving them some of the same capabilities.

The idea behind the newer, more powerful beams was pretty simple, the team acknowledges; it was figuring out how to make it happen that was difficult. The basic idea is to pack as much charge as possible into the shortest amount of time. In their work, they generated 100 kiloamps of current for just one quadrillionth of a second.

Quantum Computers Keep Losing Qubits but Scientists Just Found a Fix

Vanishing atoms can ruin quantum calculations. Scientists have a new plan to locate leaks.

Quantum computers face a major challenge: atoms, which serve as their qubits, can vanish without warning, corrupting calculations. Researchers have developed a groundbreaking method to detect this problem in neutral-atom quantum systems without disrupting their state. This discovery helps overcome a key hurdle in making quantum computing.

Performing computation using quantum-mechanical phenomena such as superposition and entanglement.

Inside the Proton: The Most Intense Forces in the Universe, Revealed

Using lattice quantum chromodynamics, researchers have created what is likely the smallest force field map ever generated. Their findings reveal astonishingly powerful interactions, akin to the weight of 10 elephants squeezed into a space smaller than an atomic nucleus.

Mapping the Forces Inside a Proton

Scientists have successfully mapped the forces inside a proton, revealing in unprecedented detail how quarks—the tiny particles within—react when struck by high-energy photons.

Scientists open door to manipulating ‘quantum light’

This quantum light manipulation breakthrough paves the way for unprecedented technologies.

Scientists from the University of Basel and the University of Sydney successfully manipulated and identified interacting packets of light energy, or photons, with unprecedented precision.

This breakthrough, published in Nature Physics, marks the first-ever observation of stimulated light emission at the single-photon level—a phenomenon first predicted by Albert Einstein in 1916.

By measuring the time delay between photon interactions, researchers demonstrated how photons could become entangled in a “two-photon bound state,” opening up new possibilities for quantum computing and enhanced measurement techniques.

This discovery has profound implications for photonic quantum computing and metrology, particularly in fields like biological microscopy, where high-intensity light can damage delicate samples. Dr. Sahand Mahmoodian, a leading researcher on the project, emphasized that harnessing quantum light could lead to more precise measurements with fewer photons. Meanwhile, tech companies like PsiQuantum and Xanadu are already exploring how this research could contribute to fault-tolerant quantum computing. As scientists refine their ability to manipulate quantum light, the door opens to a future of more powerful computing, ultra-sensitive sensors, and revolutionary advancements in technology.

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Scientists Bend Light Through Time in a Quantum Leap

A recent study from the University of Eastern Finland (UEF) examines how photons—the fundamental particles of light—behave when they encounter sudden changes in a material’s properties over time. This research reveals intriguing quantum optical effects that could advance quantum technology and help establish an emerging field known as four-dimensional quantum optics.

Four-dimensional optics is a field of research that explores how light interacts with structures that change both in time and space. This emerging area has the potential to revolutionize microwave and optical technologies by enabling capabilities such as frequency conversion, amplification, polarization control, and asymmetric scattering. Because of these possibilities, it has drawn significant interest from researchers worldwide.

In recent years, substantial progress has been made in this field. For example, a recent international study published in Nature Photonics.

Supercomputer Cracks the Code of Shapeshifting Atoms

Using the Frontier supercomputer, researchers have cracked a major challenge in nuclear physics: accurately predicting nuclear structure and forces at an unprecedented level of detail.

Their discoveries, including new insights into the shape-shifting nature of the 30-neon nucleus, could revolutionize scientific fields ranging from quantum mechanics to national security.

Revolutionizing Nuclear Predictions with Frontier.

Atomically thin NbSe₂ demonstrates resilient superconducting fluctuations

Superconductivity is an intriguing property observed in some materials, which entails the ability to conduct electric current combined with an electrical resistance of zero at low temperatures. Physicists have observed this property in various solid materials with different characteristics and atomic thicknesses.

A team of researchers at Nanjing University in China recently carried out a study aimed at further exploring the behavior of niobium diselenide (NbSe₂), a layered material that has been found to be a superconductor when it is atomically thin. Their paper, published in Physical Review Letters, unveils resilient superconducting fluctuations in atomically thin NbSe₂, which could play a part in the anomalous metallic state previously observed in this material.

“Our study was inspired by a long-standing puzzle in condensed matter physics, which can be summarized by the question: can metals truly exist in two dimensions as the ground state?” Xiaoxiang Xi, senior author of the paper, told Phys.org. “While we understand the behavior of everyday metals and insulators, ultrathin materials—like sheets just one atom thick—challenge these conventional rules.”

Graphyne’s transformation: A new carbon form with potential for electronics

Graphyne is a crystalline form of carbon that is distinct from both diamond and graphite. Unlike diamond, where each atom possesses four immediate neighbors, or graphite, where each atom has three, graphyne’s structure combines two-coordinate and three-coordinate carbons.

Computational models suggest that graphyne has highly compelling electronic, mechanical and . It is predicted to be a semiconductor with a band gap appropriate for electronic devices, ultra-high charge carrier mobility far surpassing that of silicon, and ultimate strength comparable to that of graphene.

Applications of graphyne in electronics, energy harvesting and storage, gas separations and catalysis have been proposed. While graphyne was first theoretically predicted more than three decades ago, its remained elusive.