Terahertz spectroscopic technique for characterizing the microwave dielectric properties of Ba(Mg1/3Ta2/3)O-3 materials

We have measured the complex index of refraction of Ba(Mg1/3Ta2/3)O-3, BMT, ceramics using coherent terahertz(THz) time domain spectroscopy. The diele ctric properties of BMT ceramics, which were prepared via a two-step mixed oxide process or a hot isostatic press (HIP) process in 0.1-0.6 THz regime were studied. The real part of the index of refraction of BMT prepared via a two-step process was about 5.04, whereas that of BMT materials prepared v ia a, HIP process was around 4.97. These values are similar to the real par t of the index of BMT ceramics in the microwave range (n=5.0). Hipped BMT m aterials exhibit much larger power loss and hence lower Q-factor than two-s tep mixed oxide processed BMT in 0.1-0.6 THz regime. (C) 2001 Published by Elsevier Science Ltd. All rights reserved.