Proving direct band gap property of a semiconductor

[hasniali]

Hi,
How can I prove direct band gap property of a Transition Metal Dichalcogenide electrically and optically through experimentation? I can use PL measurements to prove this for optical band gap. Is there any other equipment or technique to prove this? I can not use ARPES because channel length is around 5 um. I think ARPES requires larger films. I am using scotch tape method for exfoliation. Any help in this regard is highly appreciated. Thank you.

 

[Henryk]

Another way is Band edge absorption spectroscopy. Absorption curve is much sharper for direct band semiconductors.
See this:

https://www.researchgate.net/post/How_can_you_know_the_material_is_of_direct_band_gap_or_indirect_bandgap