First you should specify wich country you will use it, take in mind that all I'm about to say is valid to Spain, but it's not sure for other countries.
There are many ways of writing these type of things. If the principal subject of the email is the research, I'd save useless formalities or introductions, and go straight to the point, for instance:
Recientemente he leído sus investigaciones y he pensado que/estoy de acuerdo con/pienso que...
Even if the principal subject is the research but you still want something like an introduction, maybe you want to speak about something else first for example, there are several well-known "formulas" to begin to speak about a certain subject.
If it's the first thing you are writing in the email:
Le escribo la/el presente para comunicarle/expresarle que...
The "la/el" article isn't THAT important here, since the forumla comes from old letters that was "la carta" and some people still use that femenine article instead of the masculine article that email have in Spanish.
Also comunicarle should be used only for really formal things, even legal things. Speaking about a research you could use it if he/she win an award f.i., but you'd use expresarle or other more appropiate word to express your opinions and such.
Still if the subject is the first thing in the email, but if it's some sort of legal or super formal communication/letter:
Por la presente le comunico que...
Or
Por la presente, y en representación del Consejo de Dirección de la Universidad X, le comunico que...
If the subject isn't the first thing in the email so you want to change the subject, the con respecto formula Krauss told you in his answer is the more formal one, but the others Krauss proposed are still perfectly usable in a formal environment! Maybe you are using the phrase more than once and you don't want to repeat yourself, or some of the formulas are more used in one country and not in the others.
Take in mind that there are some well known, frequently used, formal formulas in Spanish, but there isn't one perfect one you can use always. To be formal is more about how you write the overall letter, than whether you use that or this word in some phrase.
Well, maybe you already know this last thing :) but that's what I was trying to say.