Or, in the completely opposite fashion, bake your burgers on a wire rack at 200F until the center reads 135F, take them out to rest for 10 min, and then deep fry them.
Works well for thick burgers (almost as good as sous vide actually) but you need to grind your own meat in order to minimize the risk of getting sick from the various enteric bacteria. The oven cannot hold meat at medium rare, at least without going to extremes*, so either you'll overcook the meat or the meat will still harbor salmonella, e. coli, etc. To reduce the risk even more, blanch your whole cuts in boiling water for 10 seconds, followed by shocking in ice water, before chopping and grinding them. This is because bacteria is usually present only on the outside of a whole cut. This doesn't work if the meat has been perforated or severely lacerated in such a way that "surface area" exists where the boiling water cannot pasteurize.
* Combi ovens can accurately hold low heat. A regular oven can also do the job if you can go down to 150 F but then you need a wet-bulb thermometer inside...