Terahertz Higgs Echo Spectroscopy of a Niobium Superconductor
ORAL
Abstract
THz multi-dimensional coherent spectroscopy (MDCS) has been proven to be a powerful tool to study driven quantum systems and discover collective modes in superconductors. Here, we report the observation of robust Higgs echoes in a Niobium superconductor through phase-locked pulse-pair coherent driving using THz-MDCS. The nonlinear quantum excitation pathway of the echo signals demonstrates an unambiguous origin from Higgs mode excitation and separate the Higgs peaks from quasi-particle (QP) ones. We also reveal Higgs-Higgs interactions from the correlative modulation of the superconductor order parameter . Our quantum kinetic simulations capture the spectral-temporal features from experiment results and unravel the role of Higgs-Higgs interactions in the formation of echoes. Our discovery provides a deep insight into the exotic coherence and correlation from superconducting amplitude channels, bringing a new view of manipulating the correlated quantum systems.
*This work was supported by the Ames National Laboratory, the U.S. Department of Energy, Office of Science, Basic Energy Sciences, Materials Science and Engineering Division under contract No. DEAC0207CH11358.
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Presenters
Chuankun Huang
Iowa State University
Authors
Chuankun Huang
Iowa State University
Martin Mootz
Iowa State University, Ames National Laboratory
Liang Luo
Ames National Laboratory, Ames Laboratory
Yihua Qiang
Iowa State University, Ames National Laboratory / Iowa State University
Victor Quito
Iowa State University
Peter P Orth
Ames National Laboratory and Iowa State University, Iowa State University, Ames National Laboratory / Iowa State University
