How uncommon or weird is it to put my citations in a powerpoint slide at the title ? I really want to put the citations in the slide and not only at the very end.
Slides are different beasts from papers and the style should match the medium. For example, we usually enumerate equations in papers, but shall we do it on slides? Clearly, readers can not go back until the presenter himself does it, so why wasting space on numbers in the first place?
Applying it to your example: why would you need
? Simply put reference if you feel it's needed. Or symbolise,
[Kingma et al 2015].
For a presentation, such citations are entirely useless. The very structure of presentation means that the audience cannot move around in a presentation and scroll into the future to look up what something refers to. As Dmitry Savostyanov points out, references on the slide like (A.N. Person 2016) gives some partial information that might be of use to informed audiences or introduce other characters of the story of research. They do have the advantage that they can be viewed at the appropriate time in the presentation.
Now I was discussing presentations, not slides. Some people distribute slides as handouts and handouts can be read in a nonlinear way at the time and convenience of the reader. Putting such citations in the title might well make the slide into a better handout- but certainly into worse presentation slides. Slides are generally suboptimal as handouts. Since you are using LaTex, it should be easy for you to make proper handouts out of your slides if you want handouts, and if you are willing to put in the effort, you can use the advantages of ordinary written communication there. If someone is stuck in using something like PowerPoint and wants handouts, but is too lazy to produce handouts, one should at least have two sets of slides, with the one for presentations not containing useless references the audience cannot access at the time of occurence.
It would be better to introduce that reference giving to it some seconds of your talk. If it is in title, that should be the frame or the motivation of the work. Nothing wrong but I find it bit weird. However it will surely attract the attention. But nowadays everyone will start searching it instead of listening to you.