Conduction band states in AlP/GaP quantum wells

We report on the investigation of the conduction band (CB) of AlP by high magnetic field cyclotron resonance (CR) and transport in a two-dimensional electron gas (2DEG) confined in AlP/ GaP. We found that for QW width 10nm thick, the ground state becomes twofold Xxy valleys with cyclotron mass m xy c /m0= 0.52±0.01. We conclude that the bulk AlP CB displays three ellipsoidal valleys having minima at the X point of the Brillouin zone (BZ) with transverse and longitudinal effective masses mt/m0 = 0.3±0.02 and ml/m0 = 0.9±0.02.