Quantum-inspired advances transform crystal gaps into terabyte storage for classic memory

From punch card manipulation looms in the 1800s to modern mobile phones, if an object has an “on” and “off” state, it can be used to store information.

In a computer laptop, the binary one and zero are transistors that run at low or high voltage. On a compact disc, one is where the small indented “pits” turn into flat “lands” or vice versa, and zero is when there is no change.

Historically, the size of objects that create “one” and “zero” has limited the size of storage devices. However, researchers at the University of Chicago Pretzker’s Department of Molecular Engineering (Uchicago PME) have now explored methods to create zeros from crystal defects.

Their research was published today in Nanophotonics.

“Each memory cell is a single missing atom and a single defect,” Uchicago PME Asst said. Professor Tian Chang. “Now we can pack terabytes of bits into a small cubes of material just millimeters in size with terabytes.”

This innovation is a true example of Uchicago PME’s interdisciplinary research using Quantum Techniques to revolutionize classic non-mass computers and uses quantum technology to rotate the research of radiation dosimeters. . It is mostly known as a device that hospital workers absorb from X-ray panels. For groundbreaking microelectronic memory storage.

“Our work isn’t exactly quantum, but we found a way to integrate a highly functional research group in Quantum with solid-state physics applied to radiation survey measurements,” said Zhong’s postdoctoral research. Leonardo França, the person who is a member of the country, said: “There is demand for people who are doing research on quantum systems, but at the same time there is demand for improving the storage capacity of classic nonvolatile memory. The work is grounded.”

From radiation measurements to optical storage

This study was launched during Franca’s PhD. Research at the University of Sao Paulo, Brazil. He was studying radiation survey meters, a device that passively monitors the amount of radiation workers in hospitals, synchrotrons and other radiation facilities.

“For example, hospitals and particle accelerators need to monitor how much radiation is exposed to,” Fransa said. “There are some materials with this ability to absorb radiation and store that information for a certain period of time.”

He was immediately fascinated by the way that he could manipulate and “read” the information through optical techniques of drawing light.

“When a crystal absorbs enough energy, it emits electrons and holes. These charges are captured by defects,” Fransa said. “You can read that information. You can emit electrons and read the information through optical means.”

Fransa quickly saw the potential for memory storage. He took this non-quarterly job to Zhong’s Quantum Institute and created interdisciplinary innovations using quantum technology that constructs classical memory.

“We are creating a new type of microelectronic devices, quantum-inspired technology,” says Zhong.

rare earth

To create a new memory storage technology, the team added “rare earth” ions to the crystals, a group of elements also known as lanthanides.

Specifically, they used rare earth elements called Praseodymium and Oxidated Yttrium crystals, but the reported processes can be used in a variety of materials, taking advantage of the strong and flexible optical properties of rare earths.

“It is well known that rare earths present specific electronic transitions, from ultraviolet to near-infrared regimes, where they can select a specific laser excitation wavelength for optical control,” Fransa said.

Unlike dosimeters that are usually activated by x-rays or gamma rays, here the storage devices are operated by a simple ultraviolet laser. The laser stimulates the lanthanide, which releases electrons. Electrons are trapped in some of the defects in the oxide crystals, such as individual gaps in structures that require, for example, a single oxygen atom, but not in other ways.

“It’s impossible to find crystals in natural or artificial crystals. It’s defect-free,” Fransa said. “So what we’re doing is taking advantage of these flaws.”

These crystal defects are often used in quantum studies where they are intertwined to create “Qubits” in gems ranging from extended diamonds to spinels, but the Uchicago PME team has discovered another application. They were able to guide when the defect was charged and not. By designating the charged gap as “one” and “zero” as uncharged gaps, we were able to turn Crystal into a powerful memory storage device at a scale not seen in classical computing .

“With that millimeter cube, these memories showed that at least about a billion memories (classical, traditional memories) are based on atoms,” Zhong said.