The short version of what I do is that I work with quantum mechanics, which is the study of atom-sized objects. Quantum mechanics is very interesting for its many results which defy common sense experiences. For instance, an atom may be in two places in once ... not just "here" or "there" but both "here" and "there" at the same time! At least that is possible until somebody tries to measure where that atom is, in which case the atom suddenly decides to be in one place or the other. So measurement has an important and non-intuitive place in understanding what happens to such small objects, and is a large factor in the studies I am working on. Perhaps the most interesting result from quantum mechanics though is the fact that it has all been verified to be true in real-world experiments!
Many of the ideas behind my research actually involve understanding some of the subtleties associated with how these measurements fit into quantum mechanics. What happens for instance if I only peek at the atom instead of directly looking at it? Well, interestingly, the mathematics also covers this case, and the results can lead to even more circumstances which are also outside our everyday notion of how things should behave. Perhaps at some point I will expand on this idea with more details, but for now I refer to our lab group web page for further information about the portions relevant to our particular work.
Anyhow, for me one of the important aspects of my work is that it is much more than mathematics and abstract theoretical ideas. I actually use some of these effects on a daily basis in experiments. My primary scientific interest involves understanding how things work, but it's not in some abstract sense. Regardless of how beautiful an idea or theory is, we must remember that nature always gets the final decision on how correct that theory is. If carefully performed experiments do not agree with the theory, then it is the theory which is always in need of modification.
In practice, measuring an individual atom is extremely difficult and so to make things easier, my work involves a few million atoms all made to act in the same way. In essence, I am performing the same experiment a million times all at once. Not to be misled about the scope of this experiment however, it is useful to note that even a million atoms laid side-by-side would just about be able to cross the thickness of a hair.
As you might imagine, it is still very difficult to work with such small groups of atoms. Because each element in the periodic table behaves slightly differently, we first have to start by creating a container where only one type of element is allowed in. For somewhat historical reasons, our group uses the 55th element in the periodic table, which is known as "cæsium". Our next problem is that at room temperature, these cæsium atoms are moving at about 300 miles per hour (135 m/sec) which is way too fast to study! Fortunately a technique exists (for which the 1997 Nobel prize in physics was awarded) which allows us to cool these atoms very efficiently until they move at a snail's pace of only 0.03 miles per hour (1.25 cm/sec). This corresponds to a temperature of less than -459 °F (-273 °C)! Our refrigerator is also impressive in that it is all done with laser beams and magnetic fields inside a clear glass container and can cool the atoms in only a few seconds time. The down side to this refrigerator is that it only works with very tiny amounts of cæsium atoms and therefore can't be used to cool your beverage.
After mastering these techniques, we finally have the starting point for our experiments. The laser beams and magnetic fields used to cool the atoms in the first place turn out to be the main tools we have during the experiment as well. Laser light is what we use to watch the atoms and therefore performs the important measurement discussed earlier. In the most recent experiment, the laser light serves an additional role by helping (along with weak magnetic fields) to create some interesting behavior in the atoms that is worth watching. In the end, the goal is to use all the theoretical and experimental tricks we have available to learn as much as possible about the strange quantum behavior of our cæsium atoms.
What makes this work the most enjoyable to me is the understanding of what is going on, and for me, understanding means knowing how everything interconnects. While I certainly can use the proverbial "black box" to make a widget, I much prefer to know what is inside that box and then try and find a way to make a better widget or perhaps some other creation. No matter how well something is done, there is always a more efficient way of doing things in the real world and in the complex experiment I have been working on, there is certainly always room for improvement. The fun is not only the physics I learn about the atoms, but the practical details I learn about other aspects of nature by having to deal with all the nitty-gritty details of the experiment.
As a graduate student, I have to admit the pay is relatively low, and the school turns right around to take some of that money back, but in the end that is not very important because I thoroughly enjoy the work I do. I believe that the best path to satisfaction in one's life is finding a job one enjoys. Perhaps more appropriately, it should be said that happiness comes from finding the enjoyable parts of one's work, regardless of what the job actually is. I always take this philosophy with me to every job I have* and it has always worked!