  The recent advances in nanowire (NW) growth technology have made possible the
growth of more complex structures such as core-multi-shell (CMS) NWs. We
propose the approach for calculation of electron subbands in cylindrical CMS
NWs within the simple effective mass approximation. Numerical results are
presented for ${\rm GaAs/Al_{0.3}Ga_{0.7}As}$ radial heterostructure with
AlGaAs-core and 4 alternate GaAs and AlGaAs shells. The influence of an
effective mass difference in heterolayers is discussed.
