※このページは北大数学COEで作成しています
第５回諸分野のための数学研究会 (北大数学COE協賛)
Seminar on Mathematics for various disciplines
Program
- 日 時：
- 2006年4月19日(水) 10:30-11:30
- 場 所：
- 東京大学大学院 数理科学研究科056号室
※会場へのアクセスは下記にてご確認下さい。
駒場アクセスマップ
http://www.u-tokyo.ac.jp/campusmap/map02_02_j.html
駒場キャンパス数理科学研究科棟
http://www.u-tokyo.ac.jp/campusmap/cam02_01_27_j.html
- プログラム：
-
- 横山 悦郎 (学習院大学)
- Oscillatory growth of a crystal controlled by interface kinetics and transport process
- ABSTRACT:
- Periodic texture in a crystal -such as growth banding and growth striations- are believed to be caused by oscillatory growth. The origin of oscillatory growth falls into two categories, i.e., external and internal. Since the growth rate of a crystal depends strongly on the growth conditions, periodic changes of external conditions, such as temperature, concentration, convection etc., are common reasons for explaining oscillatory growth. On the other hand, it is thought that oscillatory growth can also have an internal cause, but there is no clear understanding. In this talk we propose the hypothesis of a hysteresis behaviour of growth rate to explain the formation of periodic structures of a growing crystal without a change of external conditions. Recently, evidence for our hypothesis is observed not only in the growth of a crystal but also in the motion of steps on the surface of crystals. Possibly such self-oscillatory growth can be controlled in experiments in near future.
