In my university, PhD students usually talk 3 years to finish their thesis and got PhD. However, I worked very hard, and I finish all courses required and my thesis and I can get my PhD within two years of starting my PhD program. My advisor is okay to let me graduate. I am planning to start applying for faculty positions. My Question is do you think this has a good impact or bad one when applying to tenure track faculty positions? I have been interviewed with a research committee and he asked me how I get PhD in two years.
This answer reflects a North American perspective at an R1 or R2 university - answers in other parts of the world may be different.
If I saw someone who completed a PhD in two years I would want to know things like:
- What work did they do before their PhD? (Did their prior experience make the PhD faster?)
- What were the primary contributions of their PhD? (Are the contributions significant?)
- How many of their contributions were their own versus their supervisors?
- What teaching experience do they have?
- How well will they work with other students and faculty?
- What leadership have they taken during their PhD?
There are of course many other qualifications to evaluate and questions to be asked.
Hiring a faculty member into a research/teaching position is always a bit of a gamble that they will be able to continue to do productive research and teaching. With just two years of a PhD, there may not be enough evidence of what will happen in a long-term position, and this could hurt your chances to get a position. (This also depends on the strength of the advisor and the letters of recommendation.)
In Computer Science the approximate qualification I use for a PhD is that a student has learned to do independent research. That is, they can formulate the ideas and experiments for and write a complete research paper more or less independently. (And get the paper accepted in a top-tier venue.) I'd be looking to see evidence of this in a faculty application.
So, would a two-year PhD have a good or bad impact? There isn't a single answer. It depends on the answers to the questions above and other cultural factors. But, I would look very closely at someone who had completed a PhD that quickly, as 4-5 years might be more typical in my field.