Suppose I am a novice student in a field of theoretical CS.
Is it allowed to ask for recent research papers from reputed journals to study?
In principle, questions about what's going on in a small subfield fit into the reference-request tag and can be on-topic. (More about this tag.)
A couple of potential pitfalls are:
Is it something it would make sense to ask your doctoral adviser instead? I think we do want to encourage students to communicate well with their advisers.
Is the area narrow enough? For instance,
What's new important work in complexity theory
might be considered primarily opinion-based, but
Are there any recent papers (last five years) on 1-counter automata
is more fact-based. In that case, however, there's the question
So to summarize, a good question of this kind should be fact-based, answerable, but not easily answerable by a Google search or by your doctoral adviser.