Niobium induces a superconducting gap in a semiconductor quantum well
A single peer-reviewed laboratory study coupled an indium arsenide antimonide quantum well to niobium without exposing the interface during fabrication. Electrical measurements found a gap of 1.3 meV after the semiconductor acquired superconducting behavior, alongside oscillations adjustable by voltage. The hybrid offers a platform for studying quantum devices, while the demonstrated result concerns fabricated low-temperature samples rather than a working quantum computer.
Science··Midday
Two materials share superconducting behavior
A single peer-reviewed laboratory experiment combined a semiconductor with a superconductor and measured a superconducting gap induced in the semiconductor. ETH Zurich, a Swiss research university, used indium arsenide antimonide, abbreviated InAsSb, together with niobium. The semiconductor’s low effective mass and strong interaction between electron spin and motion make the combination relevant to research on electrically controllable quantum devices.[1]
A protected interface strengthens coupling
The InAsSb surface quantum well was grown using a technique for controlled layer deposition called molecular-beam epitaxy. Niobium was then deposited in place while the interface remained protected from the surrounding environment. Preserving that surface reduced a source of disorder between the materials. Electrical transport measurements in Josephson junctions, thin regions carrying current between superconductors, found a semiconductor gap measuring 1.3 meV following its coupling to niobium.[1]
Gate voltage changes the oscillations
A planar asymmetric superconducting quantum interference device, known as a SQUID, showed oscillations associated with both its junction and loop that changed with gate voltage. This demonstrates electrical tunability in the fabricated low-temperature samples. Niobium provides an alternative to aluminum-based layers with different critical temperature and gap properties. The measurements support a hybrid research platform; topological superconductivity, a stable qubit and a fault-tolerant processor were not directly demonstrated.[1]
