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Erratum: Mott Transition in the Mass Imbalanced Ionic Hubbard Model at Half Filling[Nguyen Thi Hai Yen, Le Duc Anh, Hoang Anh Tuan, Nguyen Toan Thang and Tran Thi Thu Trang, Communications in Physics, Vol. 29, No. 3SI (2019), pp. 305-312]This paper was published on 22 October 2019 with an omission in the text of the author’s list. The author list should read asNGUYEN THI HAI YEN\(^1\), LE DUC ANH\(^2\), HOANG ANH TUAN\(^{1,3,\dagger}\), NGUYEN TOAN THANG\(^1\), TRAN THI THU TRANG\(^4\) AND NGUYEN THI HUONG\(^5\)\(^1\)Institute of Physics, Vietnam Academy of Science and Technology (VAST), Hanoi, Vietnam \(^2\)Hanoi National University of Education, Hanoi, Vietnam \(^3\)Graduate University of Science and Technology, VAST, Hanoi, Vietnam \(^4\)Ha Long University, Quang Ninh, Vietnam \(^5\)Thuy Loi University, Hanoi, Vietnam\(^{\dagger}\)E-mail: hatuan@iop.vast.ac.vnThe author’s list has been corrected as of 29 November 2019. The author’s list has been corrected in the electronic version of the journal.

The Mott - Hubbard metal - insulator transition in the half-filled mass imbalanced ionic Hubbard model is investigated using the two-site dynamical mean field theory. We find that for a fixed mass imbalanced parameter r the critical interaction Uc increases when the ionic energy \(\Delta\) is increased. In the other hand, for a fixed \(\Delta\), \(U_c\) decreases with increasing the mass imbalance. We also show the existence of BI phase in the system for the case \(\Delta \ne 0\), \(U=0\) and calculate the staggered charge density \(n_B − n_A\) as a function of the interaction for different values of the mass imbalance. Our results in the limiting cases (\(r = 1\); \(\Delta \ne 0\) or/and \(\Delta = 0\); \(r\ne 1\)) are in good agreement with those obtained from full dynamical mean field theory.

We consider a model of III-V diluted magnetic semiconductors where both of the exchange interaction between carrier and impurity spins, and the direct exchange interaction between magnetic impurities are taken into account. The magnetization as a function of temperature for a wide range of model parameters is calculated and discussed. We show that for a degenerate carrier system the suppression of the magnetization is sensitive to the antiferromagnetic coupling constant and the impurity concentration.

Using coherent potential approximation we study zero-temperature Mott transition of the half-filled Hubbard model in a two-dimensional square lattice with geometrical frustration. It turns out that the geometrical frustration reduces the gap between the Hubbard bands. As a result the metallic phase is stabilized up to a fairly large value of the on-site Coulomb interaction. We found that the critical value UC for the Mott transition is enhanced by the geometrical frustration. Our results are in good agreement with the ones obtained by the single-site dynamical mean-field theory. Mott-insulator; Hubbard model; geometrical frustration; coherent potential approx- imation.

The half-filled isotropic degenerate two-band Hubbard model is studied within coherent potential approximation. The model is characterized by an Ising-type Hunds exchange coupling, intraand inter-orbital Coulomb parameters. We found that the band degeneracy slightly reduces the Mott-Hubbard critical value UC . We reveal that the system can have two distinct critical values for Mott-Hubbard transitions.

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