PhD thesis delight

Daniel Oblak's thesis, Figure 1.3 Let me try something new: A PhD thesis review! I have absolutely no plans of making this a regular feature, but the thesis of Daniel Oblak, my buddy and former colleague at the Niels Bohr Institute, is so impressive and delightful that it deserves to be highlighted. It will be a very superficial review, though, as I will mostly comment on the nice figures and funny insider jokes — very little about the physics. So everyone should be able to follow me this time…

And they said let there be light and they built a grating stabilised external cavity diode laser.

To be perfectly honest, I have actually only read a few pages. Atomic physics is not my particular field, so there are tons of other articles and books I rather ought to spend my time reading. Besides, this thesis is a tome: 266 pages (349 counting everything) at 66 MB file size! I highly recommend you to grab it from NBI’s site, but be prepared for the download to take a while.

To get the physics out of the way first, the title of the thesis is Quantum State Engineering in Cold Caesium Atoms – An entangled tale of non-destructively induced collapse and squeezing of atomic states. It covers in extreme detail what was one of the four main experiments in Eugene Polzik’s Quantop lab during my time there. It aimed at demonstrating various effects on the spin of an ensemble of atoms due to quantum non-demolition interaction with light, using state-of-the-art atom trapping and interferometric techniques1.

In the beginning…

The students and post docs working on the project were all excellent experimental physicist who worked hard to build and operate the setup. However, it was (and still is) a very complex experiment and many things did not work as they should. Consequently, the results were rather slow to arrive compared with expectations. Daniel tells a tale of these hardships in his preface:

In the beginning vast public funding created heavenly lab-space on earth. Now the labs were formless and empty and the spirited physicists were contemplating over their future experiments. And they said let there be light and they built a grating stabilised external cavity diode laser. And they said let there be an optical table to separate the floor from the ceiling. And it was bought. And they browsed through catalogues from Thorlabs, MiniCircuits, and Farnell and populated the optical table and the racks above it and the entire floor-space below it. And they said let us invite some graduate students who are like us and let them screw, turn, solder, align, and calibrate all the equipment on the optical table, the racks above it and the entire floor-space below it. They saw all that they had made and it was very good; so they tried to optimise it to make it even better and at the end nothing worked as it should. Finally, they rested with a cup of coffee conversing about all the time they had spent, sang and played merry tunes, while at the back of their minds a certain guilt of missed-publication arose.

I haven’t read many full theses, but I have read many prefaces (and/or acknowledgements) — the place where we can usually write a bit freely about our experience as a graduate student. Daniel’s is hands down the best of them all. If you have already downloaded the thesis, at least do read that part!

The playful writing is not limited to the preface. Somewhat apropos the recent troubles in Japan, we meet the following paragraph in the thesis outline:

Oh, and I use British spelling conventions so don’t be alarmed when bumping into colours, synthesisers, fibres, centres, caesium and many more. Come to think of it one should be alarmed by an encounter with caesium… and preferably seek medical treatment.

Visual pleasures

Like the writing, the graphical design is also top notch. I appreciate great layout, typography and design and a thesis documenting 3+ years of your professional work definitely deserves to be beautifully presented. Written in LaTeX2, Daniel’s thesis already has all the fundamentals in place for a beautiful layout. It is fine-tuned with a quite pretty modified style file (which actually may be based on my own!).

Figures are kept in a clean, relatively consistent style throughout. And there are many figures. I have picked a representative sample and put them in the gallery below. Unfortunately the bitmap-based figures seem to have been too heavily compressed, so they are not as crisp as they could have.

A brief history of one of the most friendly labs in the world

A rather original and very useful feature is the timeline of the experiment on pages 11–15. Since Daniel had spent so many years in the lab and knew basically everything about the experiment, he thought that it would be a good idea to document its history. He therefore listed all the important events with exact dates: arrival and departure of people, measurements, observations, changes in the setup and publications. This timeline is perhaps what I like most of all in the thesis — it is such a great idea and I can imagine it is super useful for the new students and post docs joining the lab.

All in all, this is a monument of a PhD thesis. It certainly shows that he spent around half a year writing it. I am rather proud of my own thesis, but next to Daniel’s it seems like a simple leaflet!

Do you know of any other extraordinary PhD or master theses?


  1. Phew, I hope I didn’t lose any readers there. 

  2. If you don’t yet know LaTeX, I highly recommend you to try it out. It has a slightly sharp learning curve, but once past that you will get typesetting far superior of Word’s.