New nerve cells represent a quantum jump for regenerative therapy.
Unlike other reprogrammed stem cells, these can continue to multiply in a lab.
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Category: quantum physics – Page 693
These days, movies and video games render increasingly realistic 3D images on 2-D screens, giving viewers the illusion of gazing into another world. For many physicists, though, keeping things flat is far more interesting.
One reason is that flat landscapes can unlock new movement patterns in the quantum world of atoms and electrons. For instance, shedding the third dimension enables an entirely new class of particles to emerge—particles that that don’t fit neatly into the two classes, bosons and fermions, provided by nature. These new particles, known as anyons, change in novel ways when they swap places, a feat that could one day power a special breed of quantum computer.
But anyons and the conditions that produce them have been exceedingly hard to spot in experiments. In a pair of papers published this week in Physical Review Letters, JQI Fellow Alexey Gorshkov and several collaborators proposed new ways of studying this unusual flat physics, suggesting that small numbers of constrained atoms could act as stand-ins for the finicky electrons first predicted to exhibit low-dimensional quirks.
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Researchers from the Moscow Institute of Physics and Technology, ETH Zurich, and Argonne National Laboratory, U.S, have described an extended quantum Maxwell’s demon, a device locally violating the second law of thermodynamics in a system located 1–5 meters away from the demon. The device could find applications in quantum computers and microscopic refrigerators cooling down tiny objects with pinpoint accuracy. The research was published Dec. 4 in Physical Review B.
The second law says that the entropy — that is, the degree of disorder or randomness — of an isolated system never decreases.
“Our demon causes a device called a qubit to transition into a more orderly state,” explained the study’s lead author Andrey Lebedev of MIPT and ETH Zurich. “Importantly, the demon does not alter the qubit’s energy and acts over a distance that is huge for quantum mechanics.”
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https://paper.li/e-1437691924#/
A team of researchers from Austria, Italy and Sweden has successfully demonstrated teleportation using on-demand photons from quantum dots. In their paper published in the journal Science Advances, the group explains how they accomplished this feat and how it applies to future quantum communications networks.
Scientists and many others are very interested in developing truly quantum communications networks—it is believed that such networks will be safe from hacking or eavesdropping due to their very nature. But, as the researchers with this new effort point out, there are still some problems standing in the way. One of these is the difficulty in amplifying quantum signals. One way to get around this problem, they note, is to generate photons on-demand as part of a quantum repeater—this helps to effectively handle the high clock rates. In this new effort, they have done just that, using semiconductor quantum dots.
Prior work surrounding the possibility of using semiconductor quantum dots has shown that it is a feasible way to demonstrate teleportation, but only under certain conditions, none of which allowed for on-demand applications. Because of that, they have not been considered a push-button technology. In this new effort, the researchers overcame this problem by creating quantum dots that were highly symmetrical using an etching method to create the hole pairs in which the quantum dots develop. The process they used was called a XX (biexciton)–X (exciton) cascade. They then employed a dual-pulsed excitation scheme to populate the desired XX state (after two pairs shed photons, they retained their entanglement). Doing so allowed for the production of on-demand single photons suitable for use in teleportation. The dual pulsed excitation scheme was critical to the process, the team notes, because it minimized re-excitation.
IonQ, one of many companies developing a quantum computer, has announced a new trapped ion quantum computer with 79 processing qubits. The company claims this quantum computer should beat Google’s 72-qubit quantum computer, not just in terms of number of qubits, but also in total processing performance.
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By Chinese Satellite with 24.9 billion pixels of quantum technology. It’s worth seeing! You can zoom in, zoom out when you look at it. You can clearly see every gesture, even face of pedestrians on the road.
http://sh-meet.bigpixel.cn/?from=groupmessage
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MIT researchers invented a method of shrinking objects to the nanoscale.
The team can generate structures one-thousandth the volume of the original using a variety of materials, including metals, quantum dots, and DNA.
Existing techniques—like etching patterns onto a surface with light—work for 2D nanostructures, but not 3D. And while it’s possible to make 3D nanostructures, the process is slow, challenging, and restrictive.
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