University of Utah physicists read the subatomic “spins” in the centers or nuclei of hydrogen isotopes, and used the data to control current that powered light in a cheap, plastic LED – at room temperature and without strong magnetic fields.
The study brings physics a step closer to practical machines that work “spintronically” as well as electronically: superfast quantum computers, more compact data storage devices and plastic or organic light-emitting diodes, or OLEDs, more efficient than those used today in display screens for cell phones, computers and televisions.
“We have shown we can use room-temperature, plastic electronic devices that allow us to see the orientation of the tiniest magnets in nature – the spins in the smallest atomic nuclei,” says physics professor Christoph Boehme, one of the study’s principal authors. “This is a step that may lead to new ways to store information, produce better displays and make faster computers.”
The experiment is a much more practical version of a study Boehme and colleagues published in Science in 2010, when they were able to read nuclear spins from phosphorus atoms in a conventional silicon semiconductor. But they could only do so when the apparatus was chilled to minus 453.9 degrees Fahrenheit (nearly absolute zero), was bombarded with intense microwaves and exposed to superstrong magnetic fields.
In the new experiments, the physicists were able to read the nuclear spins of two isotopes of hydrogen: a single proton and deuterium, which is a proton, neutron and electron. The isotopes were embedded in an inexpensive plastic polymer or organic semiconductor named MEH-PPV, an OLED that glows orange when current flows.
The researchers flipped the spins of the hydrogen nuclei to control electrical current flowing though the OLED, making the current stronger or weaker. They did it at room temperature and without powerful light bombardment or magnetic fields – in other words, at normal operating conditions for most electronic devices, Boehme says.
“This experiment is remarkable because the magnetic forces created by the nuclei are millions of times smaller than the electrostatic forces that usually drive currents,” yet they were able to control currents, he says.
Harnessing nuclear spins can increase the efficiency “of electronic materials out of which so much technology is made,” Boehme adds. “It also raises the question whether this effect can be used for technological applications such as computer chips that use nuclear spins as memory and our method as a way to read the spins.”
This story is reprinted from material from the University of Utah, with editorial changes made by Materials Today. The views expressed in this article do not necessarily represent those of Elsevier. Link to original source.