Abstract
In this work we investigate the effect of Ag
+
doping at Sr
2+
site in La
0.57
Nd
0.1
Sr
0.33−
x
Ag
x
MnO
3
(LNSAMO
x
,
x
= 0.00 and 0.15) system on the magnetic and magneto-electrical properties. The variation of the magnetization
M
versus temperature
T
, at 0.05 T, reveals a ferromagnetic–paramagnetic transition for all samples. All samples undergo a sharp metal–semiconductor transition at a temperature
T
ρ
, accompanying the ferromagnetic–paramagnetic transition. The maximum values of resistivity temperature coefficient (TCR) and magneto-resistance were 2.5% K
−1
and 63% at room temperature of 290 K and 305 K, respectively. The TCR value is considered as an important factor in determining the sensitivity of uncooled infrared bolometers. Most interesting is that the adjustment of the low-temperature range
ρ
–
T
revealed the presence of low-temperature peaks in the resistivity curves, attributed to the diffusion effects of grain boundaries, electron–electrons, electron–magnon, electron–phonons and the interactions between them. Overall, LNSAMO
x
polycrystalline ceramics appear promising for uncooled infrared detectors, magnetic memories or magnetic storage devices.