Scientists are using light waves to accelerate supercurrents and access the unique properties of the quantum world, including forbidden light emissions that one day could be applied to high-speed, quantum computers, communications and other technologies.

The scientists have seen unexpected things in supercurrents—electricity that moves through materials without resistance, usually at super cold temperatures—that break symmetry and are supposed to be forbidden by the conventional laws of physics, said Jigang Wang, a professor of physics and astronomy at Iowa State University, a senior scientist at the U.S. Department of Energy’s Ames Laboratory and the leader of the project.

Wang’s lab has pioneered use of light pulses at terahertz frequencies- trillions of pulses per second—to accelerate electron pairs, known as Cooper pairs, within supercurrents. In this case, the researchers tracked light emitted by the accelerated electrons pairs. What they found were “second harmonic light emissions,” or light at twice the frequency of the incoming light used to accelerate electrons.

It sounds like a riddle: What do you get if you take two small diamonds, put a small magnetic crystal between them and squeeze them together very slowly?

The answer is a magnetic liquid, which seems counterintuitive. Liquids become solids under pressure, but not generally the other way around. But this unusual pivotal discovery, unveiled by a team of researchers working at the Advanced Photon Source (APS), a U.S. Department of Energy (DOE) Office of Science User Facility at DOE’s Argonne National Laboratory, may provide scientists with new insight into high-temperature superconductivity and quantum computing.

Though scientists and engineers have been making use of superconducting materials for decades, the exact process by which high-temperature superconductors conduct electricity without resistance remains a quantum mechanical mystery. The telltale signs of a superconductor are a loss of resistance and a loss of magnetism. High-temperature superconductors can operate at temperatures above those of liquid nitrogen (−320 degrees Fahrenheit), making them attractive for lossless transmission lines in power grids and other applications in the energy sector.

Graphene has already proven itself to be a weird and wonderful material in many different ways, but its properties get even more unusual and exotic when it’s twisted – and two new studies have given scientists a much closer look at this intriguing phenomenon.

When two sheets of graphene are put together at slightly different angles, the resulting material becomes either very effective at conducting electricity, or very effective at blocking it. It’s known as ‘magic-angle’ twisted graphene, and knowing more about how and why this happens could lead to advances in high-temperature superconductors and quantum computing.

Now for the first time, scientists have mapped out a twisted graphene structure in its entirety, and at a very high resolution. They’ve also been able to get ‘graphene twistronics’ working with four layers of graphene as well as just two.

DARPA has selected seven university and industry teams for the first phase of the Optimization with Noisy Intermediate-Scale Quantum devices (ONISQ) program. Phase 1 of the program began in March and will last 18 months.

ONISQ aims to exploit quantum information processing before universal fault-tolerant quantum computers are realized, which isn’t expected for many years. The program is pursuing a hybrid concept that combines intermediate-sized quantum devices (hundreds to thousands of quantum bits, or qubits) with classical computing systems to solve a particularly challenging set of problems known as combinatorial optimization.

ONISQ seeks to demonstrate a quantitative advantage of quantum information processing by leapfrogging the performance of classical-only systems in solving optimization challenges. If successful, ONISQ could be applied to optimization problems of interest to defense and commercial industry, such as global logistics management, electronics manufacturing, and protein-folding.