Novel Raman Spectroscopy Instrumentation for Investigating Quantum Materials

Raman spectroscopy, imaging, and mapping are powerful non-contact, non-destructive optical methods to probe the fundamental physics of two-dimensional (2D) layered materials. An amazing amount of information can be quantified from the spectra such as layer thickness, disorder, grain boundaries, doping, strain, and thermal conductivity. Most interestingly for the 2D materials is that Raman efficiently probes the evolution of the electronic structure and the electron-phonon interactions as a function of temperature, laser energy, and polarization. Our unique magneto-Raman spectroscopic capabilities will be detailed, which allows for diffraction-limited, spatially-resolved Raman measurements while simultaneously varying the temperature (4K to 400 K), laser wavelength (tunability from visible to near infrared), and magnetic field (up to 9 T) to study the photo-physics of nanomaterials. Additionally, coupling to a triple grating spectrometer provides access to low-frequency phonon modes. Current results on novel 2D materials will be presented to highlight our instrumentation capabilities, including resonant Raman studies of anisotropic ReS₂, temperature- and magnetic field-dependent studies of ferromagnetic CrBr₃, and an investigation on the Raman spectra of 2D GaN.