Dielectric properties of doping-free NaMn₇O₁₂: Origin of the observed colossal dielectric constant

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R. Cabassi, F. Bolzoni, A. Gauzzi, E. Gilioli, A. Prodi, and F. Licci
Istituto IMEM-CNR, Area delle Scienze, 43100 Parma, Italy

Received 6 March 2006; revised 15 May 2006; published 26 July 2006

Thesemiconducting NaMn₇O₁₂ is a doping-free compound with several coexistent propertiessuch as orbital ordering, charge ordering, and magnetic orderings ofdifferent types. We investigated its dielectric response by means offrequency impedance measurements in the range from 20 Hz to 1 MHz. Standard measurementson metallized samples exhibit an apparent colossal dielectric constant (CDC)with an epsilon _R value of several thousands at low frequencies,but a careful equivalent circuit analysis allows one to ascribethe observed CDC to the effect of a depletion layeron the metal-semiconductor junctions. We bypass this effect by meansof a nonstandard technique employing mica linings: the resulting dielectricbehavior exhibits the presence of the charge ordering transition atT_CO=176 K and shows a net bulk dielectric constant value epsilon _R68at room temperature.

URL:	http://link.aps.org/doi/10.1103/PhysRevB.74.045212
DOI:	10.1103/PhysRevB.74.045212
PACS:	71.70.Ej; 52.25.Mq; 77.22.Gm; 72.20.-i 71.70.Ej Spin–orbit coupling, Zeeman and Stark splitting, Jahn–Teller effect (condensed matter) 52.25.Mq Plasma dielectric properties 77.22.Gm Dielectric loss and relaxation 72.20.-i Electrical conductivity phenomena in semiconductors and insulators YEAR: 2006
KEYWORDS:	sodium compounds, semiconductor materials, permittivity, metallisation, equivalent circuits, semiconductor-metal boundaries, magnetic structure

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P. Lunkenheimer, V. Bobnar, A. V. Pronin, A. I. Ritus, A. A. Volkov, and A. Loidl, Phys. Rev. B 66, 52105 (2002).
N. Biskup, A. de Andres, J. L. Martinez, and C. Perca, Phys. Rev. B 72, 024115 (2005).
F. Bolzoni, A. Prodi, A. Gauzzi, E. Gilioli, F. Licci, and M. Marezio, Phys. Rev. B 71, 52404 (2005).
E. O. Wollan and W. C. Koehler, Phys. Rev. 100, 545 (1955).
J. B. Goodenough, Phys. Rev. 100, 564 (1955).
K. S. Cole and R. H. Cole, J. Chem. Phys. 9, 341 (1941).
A. I. Ritus, A. V. Pronin, A. A. Volkov, P. Lunkenheimer, A. Loidl, A. S. Shcheulin, and A. I. Ryskin, Phys. Rev. B 65, 165209 (2002).
G. A. Samara, Phys. Rev. B 27, 3494 (1983).