  Recently the Ce-based caged-type compounds having general formula CeT2Al10
(T=Fe, Ru and Os) have generated considerable interest due to the Kondo
semiconducting paramagnetic ground state (down to 40 mK) observed in CeFe2Al10
and anomalously high magnetic ordering temperature with a spin gap formation at
low temperatures in Kondo semimetals CeRu2Al10 and CeOs2Al10. The formation of
long-range magnetic ordering out of the Kondo semiconducting/semimetallic state
itself is extraordinary and these are the first examples of this enigmatic
coexistence of electronic ground states. These compounds also exhibit strong
anisotropy in the magnetic and transport properties, which has been explained
on the basis of single ion crystal electric field (CEF) anisotropy in the
presence of strongly anisotropic hybridization between localised 4f-electron
and conduction electrons. Further they also exhibit a remarkable modification
of magnetic and transport properties with doping on Ce, or T or Al sites. In
this review we briefly discuss the bulk properties of these compounds, giving a
detailed discussion on our muon-spin-relaxation (muSR) investigations and
inelastic neutron scattering (INS) results.
