Element or emitter, both work.
Tried 'em, didn't like 'em.
Here a good thread about them:
https://www.backyardchickens.com/threads/ceramic-heat-bulb-questions.1355855/
https://www.backyardchickens.com/articles/pseudo-brooder-heater-plate.67729/
Ceramic Heating Element?
I love my DIY 'plate', make sure you get one big enough...number of birds they say will fit is over-exaggerated, just like prefab coops are.