Last Full Day In Michigan

So I have heard that some people who are reading my blog are not so interested in the physics so I will try to leave the more technical things to the end of my post.


Anyways, each of us gave presentations about what we think that we are going to do during the program. I enjoyed giving the presentation but it seemed like it was stressful for some other people. I feel like there is a lot of material that I do not understand and I hope that I will have somebody in France that will be able to answer a lot of questions.

Another thing that I am thinking about is how I will manage my time in Paris. I feel like the group mentality is leaning more towards working less and having fun more. I think that it will take a lot of discipline on my part to break myself away from the group and work. I want to be a part of everything that people are doing but one of the things that I want to get out of this summer is a really good independent research experience.   I also want to do a responsible job with studying for the GRE. It would certainly make it easier if I can get a group together that will be willing to study together.  Another person suggested that I get up early and do work in the morning.

Tomorrow, we will be traveling and I will be arriving in Paris Saturday morning  (the flight from Chicago to Paris is about eight hours).


 I spent a reasonable amount of time working on my presentation.  It was interesting to see how people did their presentations. I felt that my presentation was more serious than the other presentations. I suppose that is somewhat reflective of my attitude. I feel like I could spend another 5 to 10 hours reading these papers and I would still not understand everything. I hope that I will make time to do this. I would like to have a better idea of the research that I will be doing. The person who worked with the same professor did a theoretical project. I hope that the professor has some projects that he can suggest for me.

In my presentation, I discussed how one can make multilayer mirrors that manipulate the attosecond light pulses produced by high harmonic generation. I don't exactly understand all of the details, but the idea is that you have a laser that makes pulses on the order of picoseconds into a noble gas (like Ar,Ne) and this produces a much shorter pulse. When this pulse is looked at in the frequency domain, it consists of discrete frequencies that are odd multiples of the frequency sent into the gas. The amplitude of the frequencies start high, drop off quickly, plateau, then eventually die out. When making these pulses, one screens out most of the harmonics. The other interesting thing is that the different harmonics have a phase relationship where there is a nonzero, constant group delay dispersion. (Group delay means that for a pulse, when you break it into frequencies, the different frequencies are out of phase). Anyways, mirrors can be made to compensate for this dispersion and this results in a shorter pulse. This is because if you have a bunch of superposed harmonics in phase, you get a shorter pulse than when they are out of phase. This method can make a pulse of about 90 as and the limit of the shortest pulse is about 74 as.

Anyways, I am looking forward to getting into a routine in Paris. I hope that I will have free time to do enjoyable things in Paris. I also hope to have a close group of people to hang out there.