TY - JOUR
T1 - Dynamical mean-field theoretical approach to explore the temperature-dependent magnetization in Ta-doped TiO2
AU - Majidi, M. A.
AU - Umar, A. S.
AU - Rusydi, A.
N1 - Funding Information:
We gratefully acknowledge the full funding support to this project from Universitas Indonesia through PITTA Research Grant No. 2020/UN2.R12/HKP.05.00/2016.
Publisher Copyright:
© Published under licence by IOP Publishing Ltd.
PY - 2017/5/2
Y1 - 2017/5/2
N2 - TiO2 has, in recent years, become a hot subject as it holds a promise for spintronic application. Recent experimental study on anatase Ti1-xTa x O2 (x ∼ 0.05) thin films shows that the system changes from non-magnetic to ferromagnetic due to Ti vacancies that are formed when a small percentage of Ti atoms are substituted by Ta. Motivated by those results that reveal the ferromagnetic phase at room temperature, we conduct a theoretical study on the temperature-dependent magnetization and the Currie temperature of that system. We hypothesize that when several Ti vacancies are formed in the system, each of them induces a local magnetic moment, then such moments couple each other through Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction, forming a ferromagnetic order. To study the temperature dependence of the magnetization and predict the Curie temperature, we construct a tight-binding based Hamiltonian for this system and use the method of dynamical mean-field theory to perform calculations for various temperatures. Our work is still preliminary. The model and method may need further improvement to be consistent with known existing facts. We present our preliminary results to show how the present model works.
AB - TiO2 has, in recent years, become a hot subject as it holds a promise for spintronic application. Recent experimental study on anatase Ti1-xTa x O2 (x ∼ 0.05) thin films shows that the system changes from non-magnetic to ferromagnetic due to Ti vacancies that are formed when a small percentage of Ti atoms are substituted by Ta. Motivated by those results that reveal the ferromagnetic phase at room temperature, we conduct a theoretical study on the temperature-dependent magnetization and the Currie temperature of that system. We hypothesize that when several Ti vacancies are formed in the system, each of them induces a local magnetic moment, then such moments couple each other through Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction, forming a ferromagnetic order. To study the temperature dependence of the magnetization and predict the Curie temperature, we construct a tight-binding based Hamiltonian for this system and use the method of dynamical mean-field theory to perform calculations for various temperatures. Our work is still preliminary. The model and method may need further improvement to be consistent with known existing facts. We present our preliminary results to show how the present model works.
UR - http://www.scopus.com/inward/record.url?scp=85019714774&partnerID=8YFLogxK
U2 - 10.1088/1757-899X/188/1/012061
DO - 10.1088/1757-899X/188/1/012061
M3 - Conference article
AN - SCOPUS:85019714774
VL - 188
JO - IOP Conference Series: Materials Science and Engineering
JF - IOP Conference Series: Materials Science and Engineering
SN - 1757-8981
IS - 1
M1 - 012061
T2 - International Symposium on Current Progress in Functional Materials 2016, ISCPFM 2016
Y2 - 26 July 2016 through 27 July 2016
ER -