We study the physics of quantum and topological materials using several experimental techniques; we explore their basic physics and their application in quantum technology. Our experiments include scanning tunneling microscopy, elastic/inelastic light scattering, photoluminescence and local/non-local electrical transport in quantizing magnetic fields. We do ourselves experiments in the extreme quantum limit at temperatures down to 20 milliKelvin, static magnetic fields up to 45 Tesla, pulsed up to 100 Tesla and with infrared/Terahertz radiation from free electron lasers; for these experiments we use instrumentation at international research infrastructures.