How can i Identify heavy or light hole bands?

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Shakeel Ahmad Sofi

This link will help you to explain such phenomenon. https://www.researchgate.net/profile/Ruediger-Mitdank/post/How_to_calculate_the_effective_mass_of_electron_and_hole_in_semiconductors/attachment/5c3de804cfe4a7645511209c/AS%3A715336672370691%401547560961281/download/Charles+Kittel+-+Introduction+To+Solid+State+Physics+8Th+Edition.pdf

Muhammad Hamza El-Saba

Dear Endale,

Heavy and light hole valence bands are known from the curvature (or parabolicity) of valence bands around their top edges. Heavy holes have narrower band width, while light holes have wider bandwidth. This mathematically clear from the definition of the effective mass, which is proportional to the inverse of second derivative of E(k), with respect to the wavevectors k. As for heavy and light electrons, I have never heard about this in solid state physics, but you can use the above mentioned definition.

Endale Abebe Gudeta

Thank you Dear Muhammad Hamza El-Saba and all others

But I still have some doubts:

Is there any way to guess the coordinate where these bands exist? or shall I do the for all curvature (or parabolicity) around the band gap?

let us consider the curve (band) that contains the Hvb in fig. d, this band starts from the conduction band at Gamma point and goes to the valence band (below Ef) at the R point. But I don't understand how it is still considered as a direct band gap material.

Please any suggestion, thank you in advance

You'd only consider the first Brillouin zone (1BZ) in the band structure. Therefore consider my the minima (valleys) of conduction band(s) and maxima (inverted valleys) of valence band(s). Note that some bands have more than one valley. The energy gap the energy difference between the lowest CB valley and the highest VB inverted valleys within the 1BZ.

Thank you Dear Dr. Muhammad Hamza El-Saba

I'm using XCrysDen software to choose the high symmetry k-points from the reciprocal lattice. I assumed all the high symmetry k-points that the software generate are in the 1st BZ. In fact, Bi is doped at the center of a √2 x √2 x 2 supper cell of SnTe But I'm still in doubt about whether those k-points are in the 1st BZ or not.

I really appreciate if you share me your advice

Regards