Methods for direct (without the use of the Kramers-Kronig relations) measuring the dielectric response (dynamic conductivity and permittivity) spectra of dielectrics, conductors, and superconductors in the terahertz frequency range (0.03-1.5 THz) are described. The methods are realised by using BWO (backward-wave oscillator) spectrometers developed at the A.M. Prokhorov General Physics Institute, RAS. Dielectric measurements can be performed at temperatures from 2 to 1000 K in magnetic fields up to 8 T. The dielectric response spectra are investigated for a number of materials with properties determined by electron correlation effects: superconductors, one-dimensional conductors, heavy fermion systems, spin-ladder cuprates, and spin glasses.
- Electron correlations
- Low temperatures
- Terahertz spectroscopy
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Physics and Astronomy (miscellaneous)