Experimental techniques
Besides being the coolest thing in science, experiments are at the core of the scientific method. They provide ways for us to directly observe nature. Together with theories, experiments enable the development of models that describe how we think nature works.
Physicists view phenomena in nature as different manifestations of energy, and experimental physicists get to measure those energies. Since we can’t directly see atoms, or observe their vibration, we use indirect experimental methods. Spectroscopy works by exciting a sample with radiation at different energies (think lasers, X-rays, neutrons…), and measuring how the energy of the radiation is altered by the sample, or how it gets diffracted (‘bent’) in different directions after interacting with the sample. All we know about atomic-scale effects is based on this kind of experiment.
Here are a few experimental techniques that I’m familiar with:
Nuclear resonant inelastic X-ray scattering (NRIXS), also known as nuclear resonant vibrational spectroscopy (NRVS)
Inelastic neutron scattering (INS)
X-ray diffraction
Mössbauer spectroscopy (conventional energy-domain and synchrotron time-domain)
Transmission electron microscopy (TEM)
Laser Doppler vibrometry
Diamond anvil cells (for high-pressure experiments)
