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Quantum supercomputers with the ability to perform complex calculations, encrypt data more securely and more quickly predict the spread of viruses, maybe within closer reach thanks to a discovery by Johns Hopkins researchers.

"We've found that a certain superconducting material contains special properties that could be the building blocks for the technology of the future," says Yufan Li, a postdoctoral fellow in the Department of Physics & Astronomy at The Johns Hopkins University and the paper's first author.

The findings will be published on October 11 in Science. {module In-article}

Today's supercomputers use bits, represented by an electrical voltage or current pulse, to store information. Bits exist in two states, either "0" or "1." Quantum supercomputers, based on the laws of quantum mechanics, use quantum bits, or qubits, which do not only use two states but a superposition of two states.

This ability to use such qubits makes quantum supercomputers much more powerful than existing supercomputers when solving certain types of problems, such as those relating to artificial intelligence, drug development, cryptography, financial modeling, and weather forecasting.

A famous example of a qubit is Schrodinger's cat, a hypothetical cat that may be simultaneously dead and alive.

"A more realistic, tangible implementation of the qubit can be a ring made of superconducting material, known as flux qubit, where two states with clockwise- and counterclockwise-flowing electric currents may exist simultaneously," says Chia-Ling Chien, Professor of Physics at The Johns Hopkins University and another author on the paper. To exist between two states, qubits using traditional superconductors require a very precise external magnetic field to be applied to each qubit, thus making it difficult to operate practically.

In the new study, Li and colleagues found that a ring of β-Bi2Pd already naturally exists between two states in the absence of an external magnetic field. Current can inherently circulate both clockwise and counterclockwise, simultaneously, through a ring of β-Bi2Pd.

Adds Li: "A ring of β-Bi2Pd already exists in the ideal state and doesn't require any additional modifications to work. This could be a game-changer."

The next step, says Li, is to look for Majorana fermions within β-Bi2Pd; Majorana fermions are particles that are also anti-particles of themselves and are needed for the next level of disruption-resistant quantum supercomputers: topological quantum supercomputers.

Majorana fermions depend on a special type of superconducting material--a so-called spin-triplet superconductor with two electrons in each pair aligning their spins in a parallel fashion--that has thus far been elusive to scientists. Now, through a series of experiments, Li and colleagues found that thin films of β-Bi2Pd have the special properties necessary for the future of quantum computing.

Scientists have yet to discover the intrinsic spin-triplet superconductor needed to advance quantum supercomputing forward, but Li is hopeful that the discovery of β-Bi2Pd's special properties, will lead to finding Majorana fermions in the material next.

"Ultimately, the goal is to find and then manipulate Majorana fermions, which is key to achieving fault-tolerant quantum computing for truly unleashing the power of quantum mechanics," says Li.