Items tagged with "quantum simulation"
Thanks to Einstein, we know that our three-dimensional space is warped and curved. And in curved space, normal ideas of geometry and straight lines break down, creating a chance to explore an unfamiliar landscape governed by new rules. But studying how physics plays out in a curved space is challenging: Just like in real estate, location is everything.
Inside a material, such as an insulator, semiconductor or superconductor, a complex drama unfolds that determines the physical properties. Physicists work to observe these scenes and recreate the script that the actors—electrons, atoms and other particles—play out. It is no surprise that electrons are most frequently the stars in the stories behind electrical properties. But there is an important supporting actor that usually doesn’t get a fair share of the limelight.
Topological materials have captured the interest of many scientists and may provide the basis for a new era in materials development. On April 10, 2020 in the journal Science Advances, physicists working with Andreas Elben, Jinlong Yu, Peter Zoller and Benoit Vermersch, including JQI Fellow Mohammad Hafezi and former JQI postdoctoral researcher Guanyu Zhu (currently a research staff member at IBM T. J.
In nuclear physics, like much of science, detailed theories alone aren’t always enough to unlock solid predictions. There are often too many pieces, interacting in complex ways, for researchers to follow the logic of a theory through to its end. It’s one reason there are still so many mysteries in nature, including how the universe’s basic building blocks coalesce and form stars and galaxies. The same is true in high-energy experiments, in which particles like protons smash together at incredible speeds to create extreme conditions similar to those just after the Big Bang.
This story was prepared by the Delft University of Technology (TU Delft) and adapted with permission. The experiments described were performed at TU Delft, with theoretical and numerical contributions from JQI Fellow and Condensed Matter Theory Center Director Sankar Das Sarma and JQI postdoctoral researcher Xiao Li.
JQI Fellow Jay Sau, in collaboration with physicists from Harvard and Yale, has been studying the effects of embedding magnetic spins onto the surface of a superconductor. They recently report that the spins can interact differently than previously thought. This hybrid platform could be useful for quantum simulations of complex spin systems, having the special feature that the interactions may be controllable, something quite unusual for most condensed matter systems.
JQI researchers led by Mohammad Hafezi report detailed measurements of the transmission (how much energy is lost) and delay for edge-state light and for bulk-route light on a photonic chip.
Recently physicists led JQI Fellow Christopher Monroe have executed an MRI-like diagnostic on a crystal of interacting quantum spins. They predict that their method is scalable and may be useful for validating experiments with much larger ensembles of interacting spins.
Ions are charged particles that interact strongly via the Coulomb force, which is an attraction/repulsion that decreases as particles separate. When a handful of positively charged ions are thrown together, they repel each other, and, for an oblong ion trap, form a linear crystal. (Images of ion traps can be found in media galleries.) Each ion has two internal energy states that make up a qubit. Laser beams can manipulate the Coulomb force to create tunable, long range magnetic-like interactions, where each ion qubit represents a tiny magnet.
In quantum mechanics, interactions between particles can give rise to entanglement, which is a strange type of connection that could never be described by a non-quantum, classical theory. These connections, called quantum correlations, are present in entangled systems even if the objects are not physically linked (with wires, for example). Entanglement is at the heart of what distinguishes purely quantum systems from classical ones; it is why they are potentially useful, but it sometimes makes them very difficult to understand.