University of Minnesota
School of Physics & Astronomy

Phys 5701.001

Solid-State Physics for Engineers and Scientists

Week 6
modified 17-Feb-2018 at 12:37PM by Paul Crowell

Problem Set 4 is posted and will be due Friday, February 23rd, by 5 PM. You may either put the problem set under my office door (PAN 220) or upload a SINGLE PDF file to the class Moodle Page:

https://ay17.moodle.umn.edu/course/view.php?id=10110

The lecture on Tuesday, February 20 will cover material in the second part of Chapter 5, including the generalization of the phonon density of states, van Hove singularities, anharmonicity, and thermal transport. We will start Chapter 6 (electrons) the week of February 27.

There will not be a lecture on Thursday, February 22nd.

I cannot overemphasize the importance of the density of states, and how we start with a density of states in k-space, which is always (L/2\pi)^d, (where d is the dimensionality) and, with knowledge of the dispersion relation E vs. k, calculate the density of states with respect to energy (or frequency). Depending on the type of particles we are dealing with (phonons, electrons, etc.) the dispersion relation and hence the form of the density of states with respect to energy will vary.

In contrast, the details of the Debye calculation are not important. If you have not had statistical mechanics, do not worry about it. You should know that the acoustic phonon contribution to the heat capacity scales as (T/\Theta_D)^d (where d is the dimensionality). We will discuss the contribution from optical phonons on Tuesday.

Quiz 1
modified 14-Feb-2018 at 11:43AM by Paul Crowell

The first quiz will be available (by download from the web site) next Thursday. It will be similar in format to the quiz from last year, which is posted here. This year's quiz will only cover material up through Chapter 5 (phonons).

I will probably give you 2 hours, but I am inclined to make it closed book (so that I can ask easier questions!). You can take it when you wish and hand it in on Tuesday, February 27.

There will not be a lecture on Thursday, February 22nd.

A&M Periodic Table (goes with quiz) | Download posted 14-Feb-2018 at 11:43AM
Quiz 1 from 2017 | Download posted 13-Feb-2018 at 4:30PM

Lecture Slides
modified 15-Feb-2018 at 8:02PM by Paul Crowell

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Problem Sets
modified 15-Feb-2018 at 8:02PM by Paul Crowell
Problem Set 4 | Download posted 13-Feb-2018 at 4:24PM
Problem Set 3 | Download posted 5-Feb-2018 at 7:52PM
Problem Set 2 | Download posted 2-Feb-2018 at 12:21AM
Problem Set 1 | Download posted 16-Jan-2018 at 6:05PM
Problem Set Solutions
modified 15-Feb-2018 at 2:25PM by Paul Crowell

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Week 5
modified 14-Feb-2018 at 10:06AM by Paul Crowell

Problem Set 4 is posted and will be due Friday, February 23rd, by 5 PM. You may either put the problem set under my office door (PAN 220) or upload a SINGLE PDF file to the class Moodle Page:

https://ay17.moodle.umn.edu/course/view.php?id=10110

Reading: Kittel Chapters 4 and 5. Analogous chapters in Ashcroft and Mermin are Chapters 22 - 24.

Tuesday's lecture: Phonon dispersion relations, optical and acoustic modes, phonons and momentum

Thursday's lecture: Phonons: thermal properties

Problem Set 3 is due Thursday

Week 4
modified 8-Feb-2018 at 2:34PM by Paul Crowell

Reading: Kittel, Chapter 4. This material is covered (much more thoroughly) in Ashcroft and Mermin, Chapter 22. A&M have four chapters on phonons. Neutron scattering gets its own chapter (24) as do anharmonic effects (25).

Tuesday's Lecture: We will spend the first few minutes discussing a couple points from the problem set. After that, I will turn to topics in quantum mechanics (the PHYS 5012 students can leave at that point).

Thursday's Lecture: I will conclude the brief review of chemical bonding and then start on phonons.

Problem Set 3 will be posted shortly. It will be due Thursday, February 15th.

Week 3
modified 2-Feb-2018 at 12:21AM by Paul Crowell

Problem Set 2 is posted. It will be due Tuesday, February 6th.

Because on Thursday I mutilated the discussion of the Miller indices (hkl) in terms of the shortest reciprocal lattice vector perpendicular to a set of lattice planes, I am attaching a discussion here.

Both lectures this week will be on "core material" (i.e., no special quantum mechanics lecture). I will probably start the material in Chapter 3 of Kittel (crystal binding) in the second half of Thursday's lecture. I will have relatively little to say about this beyond what is in the text. For those looking for more, I recommend Chapters 19 and 20 of Ashcroft and Mermin.

Note on Superlattice Problem | Download posted 2-Feb-2018 at 12:21AM
Structure Factor and Intensity of the Diffraction Peaks | Download posted 30-Jan-2018 at 11:17PM
Miller indices and the Bragg condition | Download posted 27-Jan-2018 at 12:12PM

Office Hours
modified 18-Jan-2018 at 7:19PM by Paul Crowell

My office hours will be Wednesday 2:45 - 4:30 and by appointment.

Week 2
posted 18-Jan-2018 at 7:11PM by Paul Crowell

The lecture on Tuesday, January 23 will continue the "primer on quantum mechanics" from last Tuesday. I will cover Hilbert space, Dirac notation, operators, expectation values, and the matrix formulation of quantum mechanics. I will probably not get to spin.

The lecture on Thursday, January 25th will continue our discussion of crystal structure, with the concept of reciprocal space and the basics of diffraction.

Problem Set 1 will be due on Thursday, January 25th. Note that the last problem (on diffraction) does not have to be handed in this Thursday. It is on there to give you a head start on next week.

Week 1
posted 16-Jan-2018 at 6:01PM by Paul Crowell

Reading: Kittel, Chapters 1 and 2
Alternatives: Simon, Chapters 12 and 13, Ashcroft and Mermin (A&M), Chapters 4 - 7

We will spend the first two weeks on "structure and symmetry," with an emphasis on the important crystalline systems and the notion of reciprocal space. I am not going to emphasize the mathematical aspects of symmetry, such as point groups and space groups. If you are interested, Ashcroft and Mermin address these (slightly) in their Chapter 7.

The first problem set is posted. Because we are interleaving the first couple lectures on quantum mechanics, I may adjust the due date, but for the moment assume it is due Thursday, January 25.