no u cannot fit just the globes
Xenon globes require something in the order of 20000volts to ignite the gas inside the globe. For this u need ballasts and ignitors.
The easiest way to go Xenon is to buy a kit. There are quite a few on the market these days. You'll want a H7 kit
Ive fitted xenon kits to quite a few cars, and have always used xenondepot.com kits. There are quite alot of poorly made kits out there, so ignore anything sold on ebay. The xenondepot kits are very good quality, i have not had a problem with them up until recently. I fitted a kit on my Z and realised one globe was 4300K and the other was 6500K. I emailed them and they arranged DHL pickup of the wrong globe the next day
Another thing to note, dont believe the marketing hype that a kit is either Philips or Hella. No leading globe manufacturer makes these kits. They are all aftermarket jobs. They take a regular xenon globe and afix a halogen headlight base. The components themselves before modification may be from a big company though