IonQ opens a 22,000-square-foot quantum R&D hub in Boulder to accelerate next-generation trapped-ion computing systems.
Category: computing – Page 16
Careful crystallization unlocks well-ordered perovskite layers for transistors
Perovskites are a class of materials with a unique crystal structure that suits applications such as fabricating solar cells, light-emitting diodes and transistors. However, molecules in thin layers often cannot arrange themselves properly because the process proceeds too quickly. Now, an international research team led by Tomasz Marszalek from the Max Planck Institute for Polymer Research has developed a new approach to controlling low-cost solution processing, thereby improving the formation of well-ordered perovskite layers and enabling their broader application in optoelectronic devices. Their paper is published in the Journal of the American Chemical Society.
Electronics can be found in almost every device, from smartphones and televisions to washing machines. Field-effect transistors are the main building blocks of electronic circuits, and they ensure that these devices can be easily operated and fully controlled. Perovskites are a new class of semiconductor that could be suitable for transistor applications. They contain various chemical elements, such as organic cations, divalent metal cations, and halide anions. This combination of elements enables the properties of thin perovskite films to be tailored precisely for specific applications.
Currently, their use in transistors is often unsuccessful due to a lack of control over the formation of the thin film, known as nucleation and crystallization. Therefore, researchers are attempting to organize the materials into thin, two-dimensional layers and stabilize them with organic molecules between the inorganic layers in order to control their optoelectronic properties.
Twisted WSe₂ reveals elusive charge-neutral quantum modes
Quantum materials, materials with properties that are influenced by the laws of quantum mechanics, have attracted considerable attention over the past few decades. Their unique properties make these materials advantageous for the development of numerous cutting-edge technologies, including quantum computers, highly sensitive sensors and energy-efficient electronics.
In some quantum materials, electrons strongly interact with each other, producing what are known as correlated quantum phases, states in which the behavior of individual electrons is influenced by the behavior of other electrons. These phases can give rise to desirable properties or effects, including superconductivity, magnetism and collective excitations.
Researchers at University at California at Santa Barbara recently observed charge-neutral propagating collective spin-valley modes, coordinated waves of quantum behavior that carry no electrical charge and are difficult to probe experimentally, in the two-dimensional (2D) semiconductor twisted tungsten diselenide (WSe2).
Roadmap charts three paths to room-temperature quantum materials for cooler computing
Imagine a laptop that never gets hot, a phone that holds its charge for days, or a computer memory chip designed to permanently retain data, even when the power goes out. This is the possibility sitting inside a remarkable family of materials that a team of researchers from the University of Ottawa and the Massachusetts Institute of Technology (MIT) has spent years trying to understand, and they just published a comprehensive roadmap of the field to date in the journal Newton.
Magnetic topological materials sit at the crossroads of magnetism and topology in modern physics. Topology is the mathematical study of shapes that cannot be continuously deformed into one another. In these materials, that idea protects the flow of electrons in a way that normal materials simply cannot.
“Magnetic topological materials offer a unique platform where magnetism and quantum physics work together in ways we are only beginning to fully understand,” explains Hang Chi, Canada Research Chair in Quantum Electronic Devices and Circuits and Assistant Professor at uOttawa’s Department of Physics. “This review brings together the field’s most significant advances and gives researchers a shared foundation to build on.”
Reanalyzed Hubble data challenges Europa plume claims
Dr. Kurt Retherford: “The new data has made us reconsider the strength of the previous paper’s conclusion regarding water vapor plumes.” [ https://www.labroots.com/trending/space/30560/reanalyzed-hub…e-claims-2](https://www.labroots.com/trending/space/30560/reanalyzed-hub…e-claims-2)
What can the vapor plumes on Jupiter’s moon Europa teach scientists about the small moon’s atmosphere? This is what a recent study published in Astronomy & Astrophysics hopes to address as a team of scientists investigated the origins of Europa’s vapor plumes. This study has the potential to help scientists better understand the geological activity occurring on Europa and how its subsurface ocean could influence the small moon’s fragile and thin atmosphere.
For the study, the researchers analyzed data obtained from NASA’s Hubble Space Telescope in 1999 and between 2012 and 2020 that displayed evidence of water vapor plumes from Europa and a hydrogen exosphere. An exosphere is the uppermost layer of an atmosphere and is where the atmosphere thins out and merges with the vacuum of space.
This study builds on a 2014 study published in Science from some of these same researchers that explored evidence of plume activity at Europa’s south pole. Now, this most recent study used a series of computer models to ascertain the accuracy of past Hubble data and from the 2014 study. In the end, the researchers discovered that while evidence of the hydrogen exosphere was present, evidence of water vapor plumes was not.
Jacob Barandes — “A New Formulation of Quantum Theory”
Talk by Jacob Barandes (Harvard University)
Seminar Website: https://harvardfop.jacobbarandes.com/
YouTube Channel: / @foundationsofphysicsharvard.
Foundations of Physics @Harvard Seminar Series.
April 12, 2023.
Abstract: In this talk, I will present a novel, exact correspondence between stochastic-process theory and quantum theory. On the one hand, this stochastic-quantum correspondence means that one can use the Hilbert-space tools of quantum theory to model real-world stochastic processes beyond the usual Markov approximation, generalizing previous stochastic approaches to quantum theory as well as potentially opening up new applications for quantum simulators and quantum computers. On the other hand, the stochastic-quantum correspondence implies that one can replace the instrumentalist textbook axioms of quantum theory with much more physically transparent axioms. The result is a clearer physical picture underlying quantum theory that is consistent with the standard no-go theorems, helps clarify the meaning of signature features of quantum theory like interference and entanglement, and has potential implications for addressing the measurement problem.
Science beyond the physical
For centuries, we’ve assumed that science has banished the transcendent and established that reality is entirely physical. But critics argue there are signs that a rigorous materialism might be holding science back. Increasingly, “emergence” is used to account for everything from consciousness to spacetime – a convenient placeholder for what materialist science may be unable to explain. Physicists like Heisenberg and Hawking concluded that science gives us models of reality, rather than final descriptions of its true nature, while there are scientists working in everything from biology to computer science who suggest that dualism is a productive metaphysical framework for their research. Materialism may have enabled science to reach beyond the dogmas of religion, but there are now those who are restlessly probing the limits of materialism itself.
Optical meta‑conveyors enable programmable nanomanipulation along arbitrary open paths
The task of gently transporting a microscopic particle from one point to another along a winding path, and then bringing it back using nothing more than a single, compact chip is a challenge we set out to address in our new study, now published in Nature Communications.
Optical forces arising from momentum exchange during light–matter interactions have become indispensable tools in biophysics, soft matter science and micro-and nanofabrication. Among these, optical conveyors—capable of generating stable, directional optical flows—enable nanoparticle transport along predefined trajectories, offering unique advantages for drug delivery, cell sorting, and lab-on-a-chip systems. However, conventional platforms often rely on spatial light modulators to produce dynamic holograms. Such systems are bulky, constrained by limited pixel size and count, and difficult to integrate—factors that severely impede practical deployment.
Metasurfaces have recently opened new pathways for miniaturizing optical manipulation devices, thanks to their subwavelength field-shaping capabilities. Yet, most existing metasurface-based schemes still depend on radially or azimuthally uniform phase gradients, which confine the resulting optical flow to closed loops (vortex rings) due to the intrinsic geometry of vortex fields.