MICROWAVE STUDIES OF LOW CARRIER STATE IN YB4AS3

To observe the cyclotron resonance (CR) in Yb4As3, we have performed t he microwave experiments with the cavity perturbation and the simple t ransmission techniques. The CR mass is evaluated as 0.72 m(0) which is consistent with the theoretical value of about 0.7 m(0) obtained by t he recent band structure calculations for LuYb3As3, It can be conclude d that the observed CR originates from the light 4p-holes of As ions c entered at the Gamma point. (C) 1998 Elsevier Science B.V. All rights reserved.