I received my PhD in applied physics and had colleagues, collaborators, and some published work in this (very broad) field. Although I'm familiar with the programs, my advice is not specific.
The question you have to answer first is: why do you want a PhD? Is it to do science for as long as possible? Is it to contribute to the frontier of human knowledge? Is it to participate in an global research community? Is it to land a tenure track job? Or do you not know the questions and their answers (which is fine!)?
I'll offer myself as a case study. I knew I wanted to make something tangible (hence device physics / photonics), I knew I wanted to explore the possibility of continuing in academia, and I knew that I would enjoy working in industry. I structured my PhD to go for a high risk/high reward research topic (with the thinking that if it pans out, academia would be viable without having to go through an extended PhD and multiple postdocs, which was off the table for me). I also set up to consult on industry projects, and started poking around the local startup incubators and B-school entrepreneurial offerings. My school (and PI) choice was motivated really by these factors: how I judged the impact of potential research being done by the team, how plugged-in and amenable was the environment to extracurricular work, and how supported I would be to a transition to start-ups/industry.
Figure out what you want, and treat your PhD itself as an experiment w/ testable hypotheses. If you're not sure about something, how can you build into the experience a way to find out? Is it a class, a side-project, the local community that can help? There are many factors to take into account when choosing a school because we all weigh those factors differently - once you decide what's really important to you you'll get better-tuned advice.
The question you have to answer first is: why do you want a PhD? Is it to do science for as long as possible? Is it to contribute to the frontier of human knowledge? Is it to participate in an global research community? Is it to land a tenure track job? Or do you not know the questions and their answers (which is fine!)?
I'll offer myself as a case study. I knew I wanted to make something tangible (hence device physics / photonics), I knew I wanted to explore the possibility of continuing in academia, and I knew that I would enjoy working in industry. I structured my PhD to go for a high risk/high reward research topic (with the thinking that if it pans out, academia would be viable without having to go through an extended PhD and multiple postdocs, which was off the table for me). I also set up to consult on industry projects, and started poking around the local startup incubators and B-school entrepreneurial offerings. My school (and PI) choice was motivated really by these factors: how I judged the impact of potential research being done by the team, how plugged-in and amenable was the environment to extracurricular work, and how supported I would be to a transition to start-ups/industry.
Figure out what you want, and treat your PhD itself as an experiment w/ testable hypotheses. If you're not sure about something, how can you build into the experience a way to find out? Is it a class, a side-project, the local community that can help? There are many factors to take into account when choosing a school because we all weigh those factors differently - once you decide what's really important to you you'll get better-tuned advice.