The electronic and optical properties of many solid-state materials are governed by complex interactions between competing degrees of freedom. Quantum materials are those with complex and correlated electronic physics that dominate the observed electronic properties. This is in contrast with traditional semiconductors where the electronic excitations are commonly described as non-interacting quasiparticles. Quantum materials include phenomena like the integer and fractional quantum Hall effects, which have been studied for decades, as well as more recently investigated phenomena like Weyl semimetals, unconventional superconductivity, and topological materials. In this talk, I will discuss our recent work on both conventional and quantum materials, with a focus on several systems, I will highlight our groups work to develop novel methods of low temperature terahertz spectroscopy with large values of the normalized energy scale, hν divided by _k_B_T_. These will enable us to study universal conductivity scaling relations of quantum materials and reveal novel ground state entanglement physics relevant to next generation quantum devices.
