Temperature-dependent evolutions of excitonic superfluid plasma frequency in a srong excitonic insulator candidate, Ta${}_2$NiSe${}_5$

Yu-Seong Seo, Man Jin Eom, Jun Sung Kim +3

We investigate an interesting anisotropic van der Waals material, Ta${}_2$NiSe${}_5$, using optical spectroscopy. Ta${}_2$NiSe${}_5$ has been known as one of the few excitonic insu…