# Effective mass

by hokhani
Tags: effective, mass
 P: 269 I have got confused about electron effective mass in crystals. Which of the definitions below are correct? 1) When an electron is in a crystal with periodic potential, it behaves such as a free electron with effective mass $m^*$ 2) when an external force is applied on the electron in a crystal, the electron behaves such as a free electron with effective mass $m^*$
Homework
 Quote by hokhani I have got confused about electron effective mass in crystals. Which of the definitions below are correct? 1) When an electron is in a crystal with periodic potential, it behaves such as a free electron with effective mass $m^*$ 2) when an external force is applied on the electron in a crystal, the electron behaves such as a free electron with effective mass $m^*$