Chandra Mohit, Yadav Satish, Rawat Rajeev, Singh Kiran
UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore, 452001, India.
J Phys Condens Matter. 2020 Jul 8;32(29):295703. doi: 10.1088/1361-648X/ab7fdc.
The effect of Cr doping has been undertaken to investigate its effect on the structural, magnetic, dielectric and magnetoelectric properties of newly discovered multiferroics material α-MnO. The Cr doping modifies the room temperature crystal symmetry i.e. transforms from orthorhombic to cubic symmetry. Similar to α-MnO, two magnetic transitions have been observed in all Cr doped samples. The effect of Cr doping manifested on the low temperature transition. The lower magnetic transition shifted toward higher temperature (25 K for pristine to 40 K for Cr = 10%) whereas the high temperature transition decreases slightly with increasing Cr content. A clear frequency independent transition is observed in temperature dependent complex dielectric measurements for Mn Cr O (0 ⩽ x ⩽ 0.10) samples around high temperature magnetic ordering ∼80 K which corroborate the magnetoelectric coupling in these samples. Interestingly, the magnetodielectric value enhanced significantly with Cr doping and a maximum increase of ∼21% is observed for 10% Cr doped sample at 5 K around 70 kOe magnetic field.
已对Cr掺杂的影响进行了研究，以探究其对新发现的多铁性材料α-MnO的结构、磁性、介电和磁电性能的影响。Cr掺杂改变了室温晶体对称性，即从正交对称转变为立方对称。与α-MnO类似，在所有Cr掺杂样品中都观察到了两个磁转变。Cr掺杂的影响体现在低温转变上。较低的磁转变向较高温度移动（原始样品为25 K，Cr = 10%时为40 K），而高温转变随着Cr含量的增加略有降低。在MnCrO（0⩽x⩽0.10）样品的与温度相关的复介电测量中，在约80 K的高温磁有序附近观察到明显的与频率无关的转变，这证实了这些样品中的磁电耦合。有趣的是，磁介电值随着Cr掺杂而显著增强，在5 K、约70 kOe磁场下，10% Cr掺杂样品的磁介电值最大增加约21%。
