The giant dielectric tunability effect in bulk around room temperature

Extrinsic and intrinsic contributions for dielectric behavior of La2NiMnO6 ceramic

“…A step-like decrease has been observed from 5a. This giant dielectric tunability is similar with reports from Tang [11,14]. The physical mechanism can be explained as follows [26].…”

“…This value is close to that of LNMO prepared by solid state reaction [3] and the LNMO by gel combustion method [2], but much higher than others prepared by wet chemical method [4,11], which reflects the influence of the preparation method on the dielectric properties of LNMO. As the temperature decreases, the dielectric constant sharply drops around a critical temperature.…”

“…Close inspection of the dielectric properties found that a very huge difference in the reported dielectric constant for LNMO ceramic [3,4,[8][9][10][11][12][13][14]. Its dielectric properties exhibit sensitively dependence on the sintering condition, synthesis method and electrode [2].This discrepancy leads to the doubt on the intrinsic origin of the abnormal dielectric behavior.…”

Giant dielectric tunability properties of Sr and Sb co‐doped La2NiMnO6 ceramics induced by extrinsic contribution

“…The dielectric response was determined using a broadband dielectric spectrometer (Turnkey Concept 50, Novelcontrol Technologies, Germany) at various frequencies (2 kHz to 4 MHz) from 123 to 300 K with an excitation voltage of 0.05 V. 6 with a relatively weak temperature dependence has been observed at high temperatures for LNMO ceramic, which is in agreement with other studies [6,9]. As the temperature decreases, its dielectric permittivity shows a sharp drop around 175 K. With the increase of Sr and Sb content, the plateau of dielectric permittivity decreases and the drop-off temperatures shift to higher values (190 K for x ¼ 0.08 and 260 K for 0.30).…”

“…The dielectric constant monotonically decreases and the relaxor-like behavior is suppressed due to the dilution effect [15]. In 2010, Tang et al [6] first reported a high dielectric tunability in bulk LNMO around room temperature at a low electric field (4 V mm À1 ). A low electric field and a high working temperature of this material may find important applications in tunable devices.…”