Luke's conversion to dark side

I have looked and read many Star wars books but i can't find out when or in what book Luke converts to the dark side under the reborn emperor. Any help on this matter will be greatly appreciated.

Dark Empire Graphic Novel

from Dark Horse Comics

Well the emperror is resurected in the jedi sunrise books so sometime after them

dark empire indeed..

You wanted the one when luke goes to the dark side, that's it

yup. he shouldnt of converted though.. its gay