Take the 2-minute tour ×
Physics Stack Exchange is a question and answer site for active researchers, academics and students of physics. It's 100% free, no registration required.

I have calculated the dipole transition elements of electronic states $\langle a|D_1^m|b \rangle$ following the book of Cohen-Tannoudji (Complement $E_X$) and tried then to calculate from that the Rabi frequency $$\Omega_{a\to b}=\frac{1}{2\hbar}E_m \langle a|D_1^m|b \rangle.$$ But what is the direction of the E-field vector $E_m$ for the $\pi$, $\sigma^+$, $\sigma^-$ transitions?

share|improve this question

1 Answer 1

I am not 100% sure about it, but I think the directions are:

$$\vec{e}_{\sigma^+}=\frac{1}{\sqrt{2}}(\vec{e}_x+i\vec{e}_y)$$ $$\vec{e}_{\pi} =\vec{e}_z$$ $$\vec{e}_{\sigma^-}=-\frac{1}{\sqrt{2}}(\vec{e}_x-i\vec{e}_y)$$

It would be nice if people could correct any mistakes especially signs and factors.

share|improve this answer

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.