Terahertz-infrared dielectric properties of lead-aluminum double-cation substituted single-crystalline barium hexaferrite

• Terahertz-infrared electrodynamic response for Ba 0.2 Pb 0.8 Al 1-x Fe 12-x O 19 crystals (x=0.0, 1.2, 3.0, 3.3) is studied in detail. A set of THz excitations are observed and assigned to the transitions from A1-term fine structured ground state 2+ . For all 3+ concentrations, ions mainly occupy octahedral site positions. Concentration dependence Fe-O bond length established. The lowest A2u mode not soften indicating suppression possible displacive phase transition pure lightly Pb-doped BaM. Hexaferrite materials highly demanded develop manufacture electronic devices operating at radio- microwave frequencies. In light prospects their use forthcoming terahertz electronics, here, we present our results on infrared dielectric a typical representative hexaferrites family, lead-substituted M-type barium hexaferrite doped with aluminum, x 12- , (Al) = 0.0, 3.3. We uniquely large high-quality single compounds prepared by spontaneous crystallization growth technique. Our aim was explore effect aluminum substitution compounds. Systematic detailed investigations dependences terahertz-infrared (frequencies 8–8000 cm ?1 ) spectra complex permittivity temperature, 4–300 K, chemical composition, 3.3, were performed two principal polarizations electric field E- vector probing radiation relative crystallographic c -axis, namely E || ? Furthermore, phonon resonances recorded discussed. contrast undoped BaFe 12 no softening frequency 2u observed, substituted number resonance absorption bands discovered frequencies between energy levels fine-structured ( 5 E) ions. temperature aluminum-doping analyzed an account taken disorder introduced aluminum. Basing data X-ray experiments, find that concentrations ions, they 2 k positions degree iron tetrahedral substantial. Along fundamental findings, obtained broad-band properties provides information can be used development lying spectral band.