postdoctoral
adjective /ˌpəʊstˈdɒktərəl/
  /ˌpəʊstˈdɑːktərəl/
 [usually before noun]- connected with advanced research or study that is done after a PhD has been completed
- a postdoctoral student
 - postdoctoral research
 
Oxford Collocations DictionaryPostdoctoral is used with these nouns:- fellow
 - researcher
 - training
 - …