Course: ELE 441

Instructor: Mansour Shayegan

F 2019

### Description of Course Goals and Curriculum

This course provides an introduction to solid-state physics at the advanced undergraduate level. Solid-state physics is the study of the properties of solid materials and how they emerge quantum mechanically from their constituent atoms. It is the largest sub-branch of condensed matter physics, which is a primary research area in modern physics, materials science, and electrical engineering. This subject is typically first introduced to undergraduates in their third or fourth year of study. The course curriculum is quite expansive. Thematically, the course introduces a series of physical models that describe the real behavior of solids at increasingly accurate levels. For example, in the first few weeks, you study the Drude (classical) and Sommerfeld (quantum) models of solids, which assume that solids are an idealized non-interacting electron gas. Next, crystal structure and periodic potentials of real solids are introduced. Topics covered in this part include: Bloch states, band structure of insulators, conductors, and semiconductors, perturbation theory, and the tight-binding approximation. Finally, in the last few weeks of the course, the concepts of phonons and harmonic crystals are introduced. This curriculum provides a solid foundation for further coursework in condensed matter physics and materials science.### Learning From Classroom Instruction

There are three 80-minute lectures per week. This means that the course covers a lot of material, approximately 1.5 times what a normal course would cover. Lectures are very straightforward and largely follow Prof. Shayegan’s handwritten lecture notes. He posts the entire lecture notes for the course (300+ pages) at the beginning of the semester, so it’s very easy to follow along with the relevant section in class. Despite all material being posted in advance, it’s still very helpful to attend lecture, since Prof. Shayegan will often give insights not found in the written lecture notes. Prof. Shayegan lectures at a reasonable pace and is very thorough, so lecture provides the perfect opportunity for clarifying any questions you may have about the concepts covered. He is very good about ensuring that everyone in the class understands what’s going on before moving on to the next concept. In addition to lecture, there is precept once a week run by the TA. The precept essentially functions as a problem solving session where you can ask the TA questions about the homework and to go over any concepts that you need clarification on.### Learning For and From Assignments

There are 11 problem sets, an in-class midterm, and an in-class final exam. The weighting is: 20% psets, 35% midterm, 45% final. Although psets are weighted least, they are crucial for understanding course material and mastering how to apply theoretical concepts to solving physical problems. The format of most psets is “choose x out of y problems to do,” where x < y. This means that you won’t get to do every single problem on the pset. However, solutions to all problems on the pset are posted after it is due. Sometimes, problems on the pset may cover supplementary material in the textbook that was not directly covered in lecture. For the sake of time, my advice for doing the psets is to choose problems closely related to material covered in lecture, so they will be the most straightforward to do. Then, when studying for exams, you can look over the pset solutions for all the problems, including the ones you didn’t do. Both the midterm and final exam are closed-book, closed-notes, and can be challenging. The midterm is 90 minutes long, consists of 4-5 problems, and is usually given after Fall Break. The final exam is 3 hours long, also consists of 4-5 problems, and is given during exam period. On both exams, there is usually one “short answers” problem consisting of True/False parts and short calculations, and 3-4 standard exam problems similar to homework problems. However, these problems will contain scenarios you will not have seen before, so it’s important to have a good grasp of the concepts and know how to apply them to novel scenarios. For best success, I recommend reworking all the problems on each pset (even the ones you didn’t do), and writing up a study guide in the days before the exam. This will allow you to internalize a lot of the knowledge you need to do well on the exam.### External Resources

Use of the internal course resources is largely sufficient for success in this course. However, there are some external resources that you can take advantage of if you are seeking further assistance. First, you can use*Introduction to Solid State Physics*by Charles Kittel if you are stuck on a particular concept and want to see it explained in a different way than the lecture notes/course textbook. There are also additional practice problems in that textbook that you can use when studying for exams. In addition, you can seek out upperclassmen or graduate students who took the course in previous years for help on particular topics if you get stuck.

### What Students Should Know About This Course For Purposes Of Course Selection

This course requires some background knowledge of elementary quantum mechanics (PHY 208) and some statistical mechanics (PHY 301). If you have taken those two courses, this course will be a natural extension of applications to concepts learned in those courses. If you haven’t taken those courses, you might find the material more challenging, though Prof. Shayegan is very good with explaining any prerequisite concepts if necessary. I believe this course works best as a first course in condensed matter physics. The pace is much slower than the alternative, which is graduate-level condensed matter physics (PHY 525). The trade-off is that more relevant modern topics like magnetism and superconductivity are not covered here. But through this course, you will gain a solid understanding of fundamental principles in solid-state physics, from which you can build upon when studying condensed matter physics in further detail. The course can count as a departmental for both electrical engineering and physics majors, and is usually taken by a mixture of upperclass undergraduate ELE or PHY majors and first-year graduate students in the ELE department.Solid State Physics