### Transition matrix elements

Posted:

**Fri Sep 07, 2018 9:39 am**Dear Sir,

While doing the analysis of mono layer h-BN we found that it is an indirect band gap semiconductor but behaves as a direct band gap material because of the high probability of transition at K point in comparison to probability of transition for the indirect case. We need to show this using the "Transition matrix elements" fundamentally necessary to calculate the absorption spectra. We have done the Bethe Salpeter analysis of the mono layer h-BN. Can you please help me to extract the transition matrix elements from this?

Also, Is Bethe Salpeter analysis able to capture indirect transitions? If not then how can we calculate transition probability for indirect transition?

I have also calculated excitonic weights for my highest peak in the absorption spectra attached below. It is showing transitions at k point 19 and k point 16. Can you help me to find out the position of k point 19 and 16 in my band structure?

And at k point 16 it is showing transition from band 8 to band 4. What does this means?

Regards,

Sitangshu

IIIT Allahabad

While doing the analysis of mono layer h-BN we found that it is an indirect band gap semiconductor but behaves as a direct band gap material because of the high probability of transition at K point in comparison to probability of transition for the indirect case. We need to show this using the "Transition matrix elements" fundamentally necessary to calculate the absorption spectra. We have done the Bethe Salpeter analysis of the mono layer h-BN. Can you please help me to extract the transition matrix elements from this?

Also, Is Bethe Salpeter analysis able to capture indirect transitions? If not then how can we calculate transition probability for indirect transition?

I have also calculated excitonic weights for my highest peak in the absorption spectra attached below. It is showing transitions at k point 19 and k point 16. Can you help me to find out the position of k point 19 and 16 in my band structure?

And at k point 16 it is showing transition from band 8 to band 4. What does this means?

Regards,

Sitangshu

IIIT Allahabad