Skip to main content
Cornell University
LASSP -  Laboratory of Atomic and Solid State Physics

Cornell Laboratory for Atomic and Solid State Physics

Brad Ramshaw research team identify new type of superconductor

Until now, the history of superconducting materials has been a tale of two types: s-wave and d-wave.

Now, Cornell researchers – led by Brad Ramshaw, the Dick & Dale Reis Johnson Assistant Professor in the College of Arts and Sciences – have discovered a possible third type: g-wave.

Their paper, “Thermodynamic Evidence for a Two-Component Superconducting Order Parameter in Sr2RuO4,” published Sept. 21 in Nature Physics. The lead author is doctoral student Sayak Ghosh, M.S. ’19.

Electrons in superconductors move together in what are known as Cooper pairs. This “pairing” endows superconductors with their most famous property – no electrical resistance – because, in order to generate resistance, the Cooper pairs have to be broken apart, and this takes energy.

In s-wave superconductors – generally conventional materials, such as lead, tin and mercury – the Cooper pairs are made of one electron pointing up and one pointing down, both moving head-on toward each other, with no net angular momentum. In recent decades, a new class of exotic materials has exhibited what’s called d-wave superconductivity, whereby the Cooper pairs have two quanta of angular momentum.

Read more about the discovery on the Cornell Chronicle.