2D cyclotron resonance and magneto-polaron coupling to homopolar and lo phonons in the layered semiconductor InSe

Abstract We have studied cyclotron resonance of the naturally occurring 2DEG found in the layered semiconductor InSe at magnetic fields up to 30 T. At low fields the resonances are split due to disorder. At higher fields we have observed resonant “polaron” coupling not only to conventional LO phonons but also to homopolar optic phonons that modulate the layer thickness and couple via a deformation potential.