Giant magnetoelectric coupling is a very rare phenomenon that has gained much attention in the past few decades due to fundamental interest as well as practical applications. Here, we have successfully achieved giant magnetoelectric coupling in PbTi1–xVxO3 (x = 0–1) using a series of generalized gradient-corrected GGA (generalized gradient approximation), including on-site Coulomb repulsion (U)-corrected spin-polarized calculations based on accurate density functional theory. Our total energy calculations show that PbTi1–xVxO3 stabilizes in C-type antiferromagnetic ground state for x > 0.123. With the substitution of V into PbTiO3, the tetragonal distortion is highly enhanced accompanied by a linear increase in polarization. In addition, our band structure analysis shows that for lower x values, the tendency to form two-dimensional magnetism of PbTi1–xVxO3 decreases. The orbital magnetic polarization was calculated with self-consistent field method by including orbital polarization correction in the calculation as well as from the computed X-ray magnetic dichroism spectra. A nonmagneticmetallic ground state is observed for the paraelectric phase for Vconcentration (x) = 1 competing with a volume changeof 10% showing a large magnetovolume effect. Our orbital-projecteddensity of states as well as orbital ordering analysis suggest thatthe orbital ordering plays a major role in the magnetic-to-nonmagnetictransition when going from ferroelectric to paraelectric phase. Thecalculated magnetic anisotropic energy shows that the direction [110]is the easy axis of magnetization for x = 1 composition.The partial polarization analysis shows that the Ti/V–O hybridizationmajorly contributes to the total electrical polarization. The presentstudy adds a new series of compounds to the magnetoelectric familywith rarely existing giant coupling between electric- and magnetic-orderparameters. These results show that such kind of materials can beused for novel practical applications where one can change the magneticproperties drastically (magnetic to nonmagnetic, as shown here) withexternal electric field and vice versa.
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