Details

Autor(en) / Beteiligte

• Choudhury, Debraj
• Venimadhav, Adyam
• Kakarla, Chandrasekhar
• Delaney, Kris T.
• Devi, P. Sujatha
• Mondal, P.
• Nirmala, R.
• Gopalakrishnan, J.
• Spaldin, Nicola A.
• Waghmare, Umesh V.
• Sarma, D. D.

Titel

Unusual dielectric response in B-site size-disordered hexagonal transition metal oxides

Ist Teil von

• Applied physics letters, 2010-04, Vol.96 (16)

Erscheinungsjahr

2010

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• We discover that hexagonal holmium copper titanate (Ho2CuTiO6), has a unique and highly desirable combination of high dielectric constant, low losses, very small temperature coefficient, and low frequency dependence. Our first-principles calculations indicate that these exceptional properties result from a size-difference at the Cu/Ti B-site that suppresses the expected ferroelectric transition, combined with the dominance of intermediate-frequency polar vibrational modes in the dielectric response. Our results suggest that the use of such B-site disorder in alloys of hexagonal transition-metal oxides should generally result in similar robust dielectrics.