Though school may be out “forever” when summer arrives, there’s a stillness that overtakes the campus of which I am not particularly fond. At the start of this spring semester, campus is bustling. Is it ironic that campus is “alive” when frozen solid, but “dead” when it looks like this.
In St. Lawrence’s Raman spectroscopy and microscopy lab, the most potent laser illumination source comes from a neodymium-doped yttrium aluminum garnet. This is a pretty ubiquitous laser source, but I happen to like it because it also demonstrates the value of nonlinear optics: though this laser is emitting light at 1064 nanometers (in the infrared), a suitable doubling crystal can combine two of those 1064 photons together to make a shiny new 532 nm photon.