Since I started doing research 10 years ago or so, this is a question that I asked myself or talked about around me many times. It also happens to be a common question for student at the end of their PhD, faced with career choices. This recent piece by Philip Ball was an excellent reminder of the unique role of the instrument in the scientific process. There are two kind of researchers out there: some who touch upon many techniques (the majority), driven by a problem to solve, while others (the minority) are specialized in one technique only.

When doing a PhD, there is a good chance that one technique in particular will be particularly useful or relevant for the topic you are investigating. In my case, I was investigating the low-temperature surface degradation of zirconia-containing ceramic materials during my PhD. Around the end of my first year, an atomic force microscope was bought and setup in the lab.

Following the advice of my supervisor, I started playing with it, since nobody else was using it, and it turned out to be a killer technique for the phenomenon we were looking at. I spent the next two years doing almost exclusively AFM, and since we were the first ones to use it to look at the surface changes induced by the degradation, we learned a lot on the phenomenon and I ended up with a dozen peer-reviewed papers by the end of my PhD. At this point, I started looking for a postdoc position and considered applying for a CNRS or university positions, and was given what I believed was a solid advice: do not specialize in one technique. Long story short: by a series of coincidences, I get interested in freezing and eventually secured a CNRS position a few years later. I have not touched or even approached an AFM since the end of my PhD.

The blog post by Philip Ball on scientific instruments brought the original question back to my mind: it is a good idea to specialize in one technique ? Does it make it easier to get grants, papers, and a stable position ? Is it rewarding ?

Since the majority of researchers are not specialized in one technique, it is easier to see the cons, first. The first and obvious constraint is that if you want to specialize in whatever you chose, you have to be the absolute best one with it. Maybe not worldwide, but at least at the local scale or preferentially larger. Once you mastered the technique and became a reference with it (congratulations), which should take you a couple of years, depending on the technique, the bad news is that you will have to upgrade your instrument, and do so sooner rather than later. Techniques are changing rapidly (think confocal microscopy, for example). Your continuous success with it usually means that you must be up-to-date. And doing so can be very costly, in particular if you are into transmission electron microscopy, for instance. Congratulations: you just entered a never-ending race. Having an out-of-date instrument can be a killer for everything you did before and you are at the risk of becoming obsolete rapidly.

The other major con I see (and I guess this is the main view) is the difficulty of developing a research line on a medium or long-term. Looking at a particular phenomenon almost always requires a range of techniques to give you a complete picture. Each technique provides a biased look, with its one strength and limitations. It’s just one part of the story you’re trying to make sense of.

There are nevertheless many advantages of being an expert with a particular instrument. Bearing in mind what I mentioned before (about the upgrades), if you have the best instrument around, you have a unique opportunity to push the limits of the knowledge rapidly, and can do so in a number of fields or topics. Microscopes with higher magnification and/or better resolution (space or time) will let you see features never seen before. There is also an intense satisfaction of pushing the limits of the instrument you have in your hand, something academics seems to really enjoy.

Once you established yourself as an expert, you won’t have to look for samples or topics anymore. People will naturally come to you will a range of problems to solve. You are certainly saving some time here, although you are at the risk of getting lost in a myriad of samples and topics. This also means that you don’t need to look for fundings anymore (except to upgrade your instrument, see previous point. It can be even worse, actually, as getting grants for equipment only can be very tough). It becomes really easy to jump in proposals, if you provide a unique and essential contribution, without being in charge.

The main advantage I see is that you get to work on many topics, which can be both intellectually satisfying and rewarding. Since you have a dispassionate look at the problem underlying the sample you’re probing, you also get a different perspective on this particular problem.

Pushing the instrument to its limits will also make you a very valuable customer to the people who sold you the piece of equipment, since you will provide a very unique and thorough feedback. If you enter into a trust relationship with them, you can also be the first one to try new upgrades (detector, column, etc.) before they come to the market. Which will again bring you in the position of being the first to unveil cool new features/phenomenon. If you’re building your own piece of equipment, which is something physicists seem to be passionate about, you are learning a lot in the process. I recently discussed this with Jim Smay, who’s been building and selling robot-casting (3D printing) machines for many years now. He’s not getting bored of it, and told me he’s always learning something new every time he’s building a new one.

At the end of the day, I guess it comes down to personal preferences. Most people will choose a problem and not a technique, but becoming an expert in one can be a very rewarding choice and the beginning of a fruitful career. I don’t have any evidences of which one is best on the long-term to secure a permanent positions and grants and keep doing cool science. I like to touch upon many topics, and freezing is certainly greatly satisfying from this point of view. I prefer the exploration of new topics and ideas to the tedious, deep investigations on well-identified problems. We need both kind of people of course, but this will probably be the topic of a different blog post.