In a landmark achievement, an international team of researchers has successfully engineered the world’s first ideal Weyl semimetal, a quantum crystal that exhibits exotic electromagnetic properties. This innovative material, synthesized from a topological semiconductor, hosts a single pair of Weyl fermions without any irrelevant electronic states, paving the way for potential applications in terahertz devices, high-performance sensors, and low-power electronics.

The discovery, published in Nature, marks a major milestone in the decade-long pursuit of quantum materials, where researchers have been hindered by the presence of undesired electrons that obscure the unique properties of Weyl fermions. By revisiting a theoretically proposed strategy from 2011, the team has created a semimetal with a vanishing energy gap, enabling it to absorb low-frequency light and unlocking new possibilities for optoelectronics and quantum technology.

However, until now, “measuring this qubit’s spin was like trying to pick up a very, very weak light signal, like trying to squint at some dim light to determine whether the qubit was spin-up or spin-down,” Eric Rosenthal, a postdoctoral scholar at Stanford University, said.

This is where a new study from Rosenthal and his team can make a big difference. They have figured out a way to measure the spin of tin-based qubits with 87 percent accuracy, enhancing the strength of signals from these qubits to a great extent.

A tin vacancy qubit is formed when two carbon atoms in a diamond are replaced by a single tin atom. This tin center has exceptional optical properties as it emits photons in the telecom wavelength range, which is highly suitable for quantum communication applications.