Talked to the recruiters and handed in my CV during their visit to our school. After two weeks, I got the phone interview invitation. They asked me what time I'd like to be interviewed. I asked to be interviewed two weeks later.
There were two interviewers. Each of them interviewed me for about 30 minutes. After a brief introduction, they asked me to grab a paper and a pen, and write down the problem and some equations. They also asked me to derive some results, and explain how I got the solution. There was a bit of calculations; not really hard, it's more about the basic concept. But it's not easy to answer if you are not familiar with the topic.
The first interviewer asked all technical questions. The second interviewer spent half of the time chatting with me and half of the time asking technical questions. Before ending the conversation, they asked me if I have any questions. I seized the chance to chat with them about their work and the working environment. Although I didn't get the right answer to all of the questions, the overall conversation was quite smooth.
In about a week I got an email form the recruiter telling me I was accepted.