# Quantization axis

1. Aug 14, 2013

### matematikuvol

What is quantisation axis? In many books authors just say that we choose that z is quantization axis.

2. Aug 14, 2013

### vanhees71

This is just saying that you consider everything in a basis, where the [itez]z[/itex] components of angular momenta have well-determined values (eigenstates of the corresponding $\hat{J}_z$ operators).