I finished my master in physics and now want to pursue a PhD (or its equivalent), both in Germany. I did my master thesis (1 year) in the field of quantum computing at a research institute, where I continued working and now could do the PhD. This work is at the intersect of computer science and theoretical physics. I like the work and I feel like I get a lot of opportunities there. But I also feel like I lack the excitement about the work that it takes to do a PhD. I always get very excited when hearing about experimental physics. But I am not sure if I had that excitement when working there or if it is rather in the context of listing to other people only. And I feel like I risk a good job that I have for sure now. Also, I have almost no training in experimental matters. I touched maybe twice an oscilloscope. Although, I have read about a number of examples where it worked out despite a lack of experience.
On top of that, I don't want my current boss to know about my doubts about continue working in his group. I feel like it could affect our relationship very badly and maybe I want to continue working with him. He is very well connected in the community and I am afraid that if I contact someone he will hear about that.
So, there are basically two questions: 1) How do I find out if I really want to switch to experimental physics, while working a full-time job? 2) How do I do it without my boss noticing?