Feb 16

Away: I will be away from Feb 17 through Feb 19. There will be no lecture on Wednesday, Feb 18. In lieu of the cancelled office hours this week, I will have extended office hours next week.
First exam will be on Tuesday, Feb 24, 1 pm-3 pm, instead of in class on Monday, Feb. 23 as originally planned. If you have a conflict with this, please let me know ASAP.

Feb 9

Homework 3: the due date of this homework has been moved to Wednesday, February the 11th.
First Brillouin zone: this article in Wikipedia has a nice animation that illustrates why only phonon modes within the first Brillouin zone are meaningful.
Optical branches of phonons: see Fig. 2 of this paper for the dispersion relation of phonons in NaCl, including the optical and acoustic branches. Figure 1 of this article shows similar graphs for diamond and graphite. To access these papers, you will probably have to use a computer on campus, such as one in a library.

Jan 31

Homework 3 has been posted at E-Learning. It is due by the beginning of class on Monday, February 9.

Jan 28

Filled skutterudites: because I couldn't log in to the class-room computer during class today, I couldn't show the crystal structure and specific heat of a filled skutterudite. Please visit this site for the structure and this site for the specific-heat data (see the full-size images of Figs. 1 and 2). Note that the specific heat comprises a T-linear term of conduction electrons, which we will discuss in a later lecture, a T^3 term of phonons, which we will discuss Friday, plus the Einstein term, which we discussed today. To visit the second site, you will probably have to go online from the university, which is subscribed to the journal in which the results were published.

Jan 21

Homework 2 has been posted at E-Learning. It is due by the beginning of class on Wednesday, January 28.

Jan 15

The office hours for this semester will be Tuesdays and Thursdays, period 7 (1.55pm–2:45pm).
Homework 1 is due by the beginning of class on Wednesday, January 21, instead of Monday, January 19.
A colored version of lecture note 1 is avaiable at E-Learning.