Course notes





Fall 2020: PHYS 502 - Condensed Matter Physics I

Mona Berciu

  • Office hours: Mondays at 3:30pm and Tuesdays 6-8pm. If you intend to join the Tuesday office hours, please email me by 5pm so I can start a zoom window within Canvas. Office hours will not be recorded.
  • If neither of these options for office hours works for you, let me know asap.

Chengshu Li
  • Contact: chengshu AT
  • Office hours: email when appointment is needed

2:00-3:30pm on Mon. and Wed. The lectures will be live through Zoom (or Collaborate Ultra, we'll test the best option) and can be accessed through your Canvas phys502 webpage. I will record them and post them on Canvas as well, so that those of you who are abroad on very different time zones can access them when convenient. I believe you have access to Canvas through your student accounts, but please let me know if you are not familiar with it.

We will be using Piazza for ALL class discussions. You should only email me and/or Chengshu about private issues, such as questions about an assignment grade. The piazza account for our course can be accessed through the Canvas course webpage. You can also signup here.

Prerequisites: An undergraduate-level course in solid state physics, such as PHYS474.

Grading scheme:

  • 40%: best 4 of 5 graded homeworks (homework 0 will not be graded)
  • 15%: midterm 1
  • 15%: midterm 2
  • 30%: individual project


The goal of this course is to provide a graduate-level introduction to some of the fundamental concepts of condensed matter physics. The main goals are to become fluent in second quantization language; to be familiar with assumptions behind various models and when are they justified; to be able to calculate bandstructures for non-interacting electronic systems and to determine if that material is a metal or an insulator; to carry out Hartree-Fock and Random Phase Approximations for interacting electronic systems; to find the phonon spectra of various materials; to be able to characterize some of the effects of electron-phonon coupling both on the electrons and on the phonons; and to become familiar wiht the basics of the Boltzmann transport theory, the BCS theory, and how to calculate the magnon dispersion in simple magnetic systems.

It is assumed that you are familiar with the basic concepts of solid state physics (e.g. crystalline lattices, Bloch bands, Drude model etc.) as covered in a typical undergraduate solid state course such as UBC's PHYS 474. In addition, working knowledge of quantum mechanics, basic statistical physics and thermodynamics will be assumed.

Recommended books:

I will provide typed notes for all the material we will discuss in this course. I have used several books, listed below, as inspiration for these notes.

  • "Solid State Physics" by N. W. Ashcroft and N. D. Mermin: this is the standard textbook and if you are seriously considering a career as a condensed-matter physicist, you should own a copy and get very familiar with all its contents. I have not chosen it as the required textbook because it does not use second quantization notation. This notation became our "language" only after the book was written, and you need to become fluent in it if you want to be able to read modern condensed matter literature. The first 7 chapters of this book roughly cover the introductory material that I assume to be known.
  • "A quantum approach to condensed matter physics" by P.L. Taylor and O. Heinonen;
  • "Condensed matter in a nutshell" by G. D. Mahan;
  • "Introduction to solid-state theory" by O. Madelung;
  • "Quantum theory of solids" by C. Kittel,
  • whatever other books inspire you. The more you read, the more points of view you will be exposed to and that will help you build and strengthen your own framework for this field of study.

    The project:

    In normal years this would be a group project, partly to encourage interactions and friendship between students and partly as an exercise in collaborating with other people towards achieving a common goal. Given the challenges we're facing this year, I believe it is better to turn it into an individual project, to avoid complications coming from having students spread in various corners of the world.

    Your project will be a roughly 4 pages long report on a topic related to the material studied in this course. Ideally you should work on something of direct interest for your M.Sc./Ph.D. research. If you are an experimentalist, you might decide to describe your experiment or maybe focus on the theoretical framework used to explain what is being measured. Theorists are more likely to discuss additional theoretical methods, or expand on those discussed in class, or solve specific problems, but you are free to report on any aspects of experimental physics, if you wish.

    At the beginning of October I will make sure that each of you has a reasonably ambitious project. When you're making your choice, make sure that either you have a topic not covered in previous years, or that it focuses on different aspects than those covered before. Have a look at the previous projects also in order to get a feeling for the level of detail expected. The typed reports should be submitted to me by the end of the term (exact date TBD). Normally every one of you would give a live presentation but again, that could be problematic this time. So instead, we will mimic the process of submission for publication. I will randomly pick three anonymous referees for each project (thus, each of you will have to review three reports). You will then get a chance to respond to your referee reports and address the issues raised. The referees will then give your report a grade, which will be weighted towards your project grade. We will discuss this more as we go along, but the project grade will be based not just on the project itself, but also on your participation to the refereeing process both as an "author" and as a "referee".


    There will be 5 bi-weekly sets. Set 0 is a "test assignment" and will not be graded. If you can solve it without too much trouble then you are ready for this course. If not, then you should take PHYS 474 first. All other sets will be graded, however the lowest grade of the 5 will not count towards your final grade. The problem sets will be posted on-line here. To encourage you to meet and know your colleagues, one problem in each set will have a group solution, meaning that each group submits a single common solution and all students in the group receive the same mark for that problem. The remaining problems should be solved and submitted individually, and will be marked as such. I will select different groupings for the 5 assignments so that you get to meet and work with as many other students as possible. Both the group and the individual solutions should be neatly written, with problems in the order assigned. Use a scanning app such as Genius Scan to make to produce a good quality pdf file, which should be uploaded through the Canvas PHYS502 website before the deadline (end of the lecture on due date). The solutions will be posted on-line immediately after the class; as a result, late homeworks will not be accepted.

    Discussions amongst you regarding the homework problems are obviously needed for the group problems, but also very strongly encouraged for the individual ones. You should also use Piazza discussions and the office hours if you're stuck and need a bit of help - I'm always happy to discuss. However, the writing of the individual solutions must be done by each student on their own. Under no circumstances should you copy or even look at someone else's solution to a problem while writing your own homework -- if you cannot write the solution without "help", it means you have to do more work to fully learn that material! Identical homeworks will be severely penalized.

    If you fail to find the correct and complete solution to any assignment problem, immediately make sure that you understand the posted solution and are able to solve similar problems by yourself. If you cannot follow the posted solution, discuss it with me and/or with your best friends from among PHYS502 students. Do not procrastinate! Things will not get any easier later on.


    We will discuss the details once I know precisely where you are located, and what other challenges you are facing in terms of internet connectivity, appropriate work space, etc.