Giant magnetoresistance in Ce-doped manganite systems

Das, Sandip; Mandal, P.

doi:10.1007/s002570050413

Cited by 31 publications

(24 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…However, this change is offset by the overall large resistivity which makes ⌬/ small. Results for the x ϭ0.3 sample agree well with the results of Das et al [14][15][16] Magnetization and thermal expansion data reveal the CSMO sample exhibits a first order phase transition at T C ϭ43 K. The material appears to be a ferromagnetic insulator below T C and a paramagnetic semiconductor above T C , however its low temperature phase needs to be confirmed. It shows a maximum MR ratio of 40% at 41 K just below T C .…”

Section: ͓S0021-8979͑99͒35908-9͔supporting

confidence: 85%

Colossal magnetoresistance in Ce doped manganese oxides

Gebhardt

Roy

Ali

1999

Journal of Applied Physics

110

View full text Add to dashboard Cite

In this study we investigate the effects of Ce doping in R1−xAxMnO3 (R=La, Ce, and A=Sr, Ce) on the magnetic and transport properties of this system. For La1−xCexMnO3 (LCMO), an increase in Ce concentration is accompanied by an increase in TC from 225 to 236 K, as well as an increase in the electrical resistivity. An extremely high resistivity is observed in the new system Ce1−xSrxMnO3 (CSMO) which becomes insulating below its Curie temperature of 43 K. A maximum magnetoresistance (MR) ratio of 40% for CSMO and 53% for LCMO is observed. A larger change in resistivity is seen to correspond to an increase in the Ce concentration, however this is offset by an overall resistivity increase which keeps the MR ratio low. The high resistivity may be due to unreacted oxides in the samples. If true, the amount of impurity appears to be proportional to the Ce doping. If this impurity level can be reduced, a significant colossal magnetoresistance effect could be exhibited by these systems.

show abstract

Section: ͓S0021-8979͑99͒35908-9͔supporting

confidence: 85%

Colossal magnetoresistance in Ce doped manganese oxides

Gebhardt

Roy

Ali

1999

Journal of Applied Physics

110

View full text Add to dashboard Cite

show abstract

“…Then the metallic conductivity and ferromagnetism observed in RAMO have been understood as due to the double exchange (DE) between spin-aligned Mn 3+ (t 2g 3 e g 1 ) and Mn 4+ (t 2g 3 ) ions through oxygen ions. Recently the metalinsulator (M-I) transition, the ferromagnetic transition, and the colossal magnetoresistance (CMR) phenomena have also been observed in the Ce-doped manganites of La 1-x Ce x MnO 3 [1]. If Ce ions are tetravalent in La 1-x Ce x MnO 3 , then electron doping will drive the system to have the Mn 2+ -Mn 3+ mixed-valent states, unlike in the hole-doped RAMO manganites.…”

Section: Introductionmentioning

confidence: 96%

Electronic structure of La_0.7Ce_0.3MnO₃ thin film

Han

Lee

Kim

et al. 2004

Physica Status Solidi (b)

View full text Add to dashboard Cite

The electronic structure of epitaxial thin films of La 0.7 Ce 0.3 MnO 3 (LCeMO) has been investigated using photoemission spectroscopy (PES) and X-ray absorption spectroscopy (XAS). The measured valenceband PES, Ce 3d PES, and Ce 3d XAS spectra for LCeMO consistently indicate that the localized Ce 4f orbitals are almost unoccupied so that the Ce valence is nearly tetravalent. The Mn 2p XAS spectrum suggests Mn 2+ and Mn 3+ mixed-valent states of Mn ions in LCeMO. The LSDA + U calculation agrees better with the measured PES/XAS spectra than the LSDA calculation (U: the on-site Coulomb interaction).

show abstract

“…Recently, the FP and MI transition phenomena and colossal magnetoresistance (CMR) have also been observed in Ce-doped manganites La 1Àx Ce x MnO 3 [11][12][13]. Due to the electron-doped character observed in Nd 2Àx Ce x CuO 4 [14], Das and Mandal [11] proposed on the basis of DE model that corresponding amount of Mn 2þ (t 3 2g e 2 g ) ions are generated as a result of the substitution of trivalent La 3þ with tetravalent Ce 4þ ions.…”

mentioning

confidence: 98%

“…Due to the electron-doped character observed in Nd 2Àx Ce x CuO 4 [14], Das and Mandal [11] proposed on the basis of DE model that corresponding amount of Mn 2þ (t 3 2g e 2 g ) ions are generated as a result of the substitution of trivalent La 3þ with tetravalent Ce 4þ ions. They considered that the electron-like charge carriers would be responsible for the ferromagnetism and metallic conductivity of La 1Àx Ce x MnO 3 .…”

mentioning

confidence: 99%

Electronic structure studies of the perovskite oxides La_1−xCe_xMnO₃ from first‐principles calculations

Zhu

Liu

Cheng

et al. 2011

Physica Status Solidi (b)

View full text Add to dashboard Cite

Ce-doped LaMnO 3 has complicated physical properties, such as unclear valence states of Ce and Mn ions, ferromagnetismparamagnetism and metal-insulator transitions, and multiphase coexistence. To explore the ground-state properties of singlephase La 1Àx Ce x MnO 3 and obtain better understanding of the complicated physical properties of the multiphase system, the electronic and magnetic structures of La 1Àx Ce x MnO 3 are investigated by using the first principle calculations. The results show that single phase La 1Àx Ce x MnO 3 is neither a hole-doped nor an electron-doped compound. The valence states of Ce and Mn ions are predicted to be trivalent in an ionic picture. Trivalent Mn ions energetically favor an A-type antiferromagnetic ordering and insulating band structure. In comparison with the experimental studies, it is concluded that overoxygenation and multiphase coexistence in experiments switch the ground state from an antiferromagnetic insulator to a ferromagnetic half-metal.

show abstract

Giant magnetoresistance in Ce-doped manganite systems

Cited by 31 publications

References 0 publications

Colossal magnetoresistance in Ce doped manganese oxides

Colossal magnetoresistance in Ce doped manganese oxides

Electronic structure of La_0.7Ce_0.3MnO₃ thin film

Electronic structure studies of the perovskite oxides La_1−xCe_xMnO₃ from first‐principles calculations

Contact Info

Product

Resources

About

Giant magnetoresistance in Ce-doped manganite systems

Cited by 31 publications

References 0 publications

Colossal magnetoresistance in Ce doped manganese oxides

Colossal magnetoresistance in Ce doped manganese oxides

Electronic structure of La0.7Ce0.3MnO3 thin film

Electronic structure studies of the perovskite oxides La1−xCexMnO3 from first‐principles calculations

Contact Info

Product

Resources

About

Electronic structure of La_0.7Ce_0.3MnO₃ thin film

Electronic structure studies of the perovskite oxides La_1−xCe_xMnO₃ from first‐principles calculations