# High-pressure infrared spectroscopy: tuning of the low-energy excitations in correlated electron systems - Condensed Matter > Strongly Correlated Electrons

High-pressure infrared spectroscopy: tuning of the low-energy excitations in correlated electron systems - Condensed Matter > Strongly Correlated Electrons - Descarga este documento en PDF. Documentación en PDF para descargar gratis. Disponible también para leer online.

Abstract: We have extended the range of the high-pressure optical spectroscopy to thefar-infrared region keeping the accuracy of ambient-pressure experiments. Thenewly-developed method offers a powerful tool for the study of pressure-inducedphase transitions and electronic-structural changes in correlated electronsystems. The novel-type optical pressure cell, equipped with largefree-aperture diamond window, allows the measurement of optical reflectivitydown to $\omega\approx20-30$ cm$^{-1}$ for hydrostatic pressures up to$p\approx26$ kbar. The efficiency of the technique is demonstrated by theinvestigation of the 2-dimensional charge-density-wave 1$T$-TaS$2$ whoseelectronic structure shows high sensitivity to external pressure. Theroom-temperature semi-metallic phase of 1$T$-TaS$2$ is effectively extended byapplication of pressure and stabilized as the ground state above $p=14$ kbar.The corresponding fully incoherent low-energy optical conductivity is almosttemperature independent below T=300 K. For intermediate pressures, the onset ofthe low-temperature insulating phase is reflected by the sudden drop of thereflectivity and by the emergence of sharp phonon resonances.

Autor: I. Kezsmarki, R. Gaal, C.C. Homes, B. Sipos, H. Berger, S. Bordacs, G. Mihaly, L. Forro

Fuente: https://arxiv.org/