Is it correct to express PhD in brackets "(PhD)" as suffix to express the ongoing degree?
Perhaps you may have seen someone express their student status in such a way, which may work informally depending on the context (perhaps a listing of students, which may have included undergrads and masters level students, and could thus differentiate). E.g.:
SGA Special Committee of Students named Student ----------------------------------------------- Student Smith (PhD) Student Garcia (MS) Student Nahasapeemapetilon (MA) ...
And note that these examples are only appropriate in contexts where you need to communicate your state of educational attainment. Perhaps a resume, name tag at networking event, or something of that nature. It's not really appropriate socially (note the disdain in the comments), or outside of such a context.
Even in a context where you are clearly understood to be a student, it's best not just trail off with
(PhD). Fully disclose your current state of education:
Student Smith (Ph.D. expected 2020)
If you passed your comps, but did not dissertate, some may frown on this, but sometimes used to indicate one has completed all work necessary for graduation except the dissertation (and even when all hope is abandoned of ever completing):
Student Smith (ABD)
or if completion is shortly expected,
Student Smith (Ph.D. candidate)
In Brazil, it is common to see people writing "doutorando" (for PhD) and "mestrando" (for Masters) to indicate that they are in the middle of the course of their degrees. The translation for these terms would be something almost like "PhDeing" and "Meing" (none of those sound well). But this practice is not considered right, because the person has not finished anything.
Also, I agree that as a PhD student you don't really want to do that, as you have not already earned your degree. Keep up with your studies, and soon you will be able to add "PhD" with no other doubts!
At my university in the USA, we award the M.Phil degree to doctoral students who have completed their coursework and exams. When they submit their prospectus, their title changes to "doctoral candidate."
So they could write either:
- Jane Doe, BA, M.Phil
- Jane Doe, doctoral candidate
Some also use the colloquial ABD (all but dissertation) but as their advisor, I discourage this for formal settings such as their CV or on their business cards:
- Jane Doe, BA, ABD