Phys.org  September 16, 2024 Inhomogeneities crucially influence the properties of quantum materials, yet methods that can measure them remain limited and can access only a fraction of relevant observables. However, complementary techniques that can resolve higher-order correlations are needed to elucidate the nature of the inhomogeneities. And local tunnelling probes are often effective only far below the critical temperature. An international team of researchers (Germany, USA – Brookhaven, Harvard University, Cornell University, Stony Brook University, Switzerland, UK) developed a two-dimensional terahertz spectroscopy method to measure Josephson plasmon echoes from an interlayer superconducting tunnelling resonance in a near-optimally doped cuprate. The […]