Enhancement of Seebeck coefficient for SrO (SrTi O3) 2 by Sm substitution: Crystal symmetry restoration of distorted Ti O6 octahedra

Yifeng Wang, Kyu Hyoung Lee, Hideki Hyuga, Hideki Kita, Katsuhiko Inaba, Hiromichi Ohta, Kunihito Koumoto

Research output: Contribution to journalArticle

13 Citations (Scopus)

Abstract

We found that Sm3+ substitution in SrO (SrTi O3) 2 is effective in improving the Seebeck coefficient (S). The ∫S∫ value increases notably with temperature, benefiting from an enhancement of the density of states (DOS) effective mass md* from ∼3 m0 (300 K) to ∼7.5 m0 (1000 K), due to an improvement of the local symmetry of Ti O6 octahedra, enhancing the degeneracy in the Ti 3d orbitals, which form the conduction band (CB), and also to an accompanying lattice expansion, which gives rise to a higher DOS at the bottom of the CB and, consequently, a larger md*.

Original languageEnglish
Article number242102
JournalApplied Physics Letters
Volume91
Issue number24
DOIs
Publication statusPublished - 2007 Dec 20

Fingerprint

Seebeck effect
restoration
conduction bands
substitutes
augmentation
symmetry
crystals
orbitals
expansion
temperature

All Science Journal Classification (ASJC) codes

  • Physics and Astronomy (miscellaneous)

Cite this

Wang, Yifeng ; Lee, Kyu Hyoung ; Hyuga, Hideki ; Kita, Hideki ; Inaba, Katsuhiko ; Ohta, Hiromichi ; Koumoto, Kunihito. / Enhancement of Seebeck coefficient for SrO (SrTi O3) 2 by Sm substitution : Crystal symmetry restoration of distorted Ti O6 octahedra. In: Applied Physics Letters. 2007 ; Vol. 91, No. 24.
@article{31857541ee544529ae79e19f16b0739b,
title = "Enhancement of Seebeck coefficient for SrO (SrTi O3) 2 by Sm substitution: Crystal symmetry restoration of distorted Ti O6 octahedra",
abstract = "We found that Sm3+ substitution in SrO (SrTi O3) 2 is effective in improving the Seebeck coefficient (S). The ∫S∫ value increases notably with temperature, benefiting from an enhancement of the density of states (DOS) effective mass md* from ∼3 m0 (300 K) to ∼7.5 m0 (1000 K), due to an improvement of the local symmetry of Ti O6 octahedra, enhancing the degeneracy in the Ti 3d orbitals, which form the conduction band (CB), and also to an accompanying lattice expansion, which gives rise to a higher DOS at the bottom of the CB and, consequently, a larger md*.",
author = "Yifeng Wang and Lee, {Kyu Hyoung} and Hideki Hyuga and Hideki Kita and Katsuhiko Inaba and Hiromichi Ohta and Kunihito Koumoto",
year = "2007",
month = "12",
day = "20",
doi = "10.1063/1.2820447",
language = "English",
volume = "91",
journal = "Applied Physics Letters",
issn = "0003-6951",
publisher = "American Institute of Physics Publising LLC",
number = "24",

}

Enhancement of Seebeck coefficient for SrO (SrTi O3) 2 by Sm substitution : Crystal symmetry restoration of distorted Ti O6 octahedra. / Wang, Yifeng; Lee, Kyu Hyoung; Hyuga, Hideki; Kita, Hideki; Inaba, Katsuhiko; Ohta, Hiromichi; Koumoto, Kunihito.

In: Applied Physics Letters, Vol. 91, No. 24, 242102, 20.12.2007.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Enhancement of Seebeck coefficient for SrO (SrTi O3) 2 by Sm substitution

T2 - Crystal symmetry restoration of distorted Ti O6 octahedra

AU - Wang, Yifeng

AU - Lee, Kyu Hyoung

AU - Hyuga, Hideki

AU - Kita, Hideki

AU - Inaba, Katsuhiko

AU - Ohta, Hiromichi

AU - Koumoto, Kunihito

PY - 2007/12/20

Y1 - 2007/12/20

N2 - We found that Sm3+ substitution in SrO (SrTi O3) 2 is effective in improving the Seebeck coefficient (S). The ∫S∫ value increases notably with temperature, benefiting from an enhancement of the density of states (DOS) effective mass md* from ∼3 m0 (300 K) to ∼7.5 m0 (1000 K), due to an improvement of the local symmetry of Ti O6 octahedra, enhancing the degeneracy in the Ti 3d orbitals, which form the conduction band (CB), and also to an accompanying lattice expansion, which gives rise to a higher DOS at the bottom of the CB and, consequently, a larger md*.

AB - We found that Sm3+ substitution in SrO (SrTi O3) 2 is effective in improving the Seebeck coefficient (S). The ∫S∫ value increases notably with temperature, benefiting from an enhancement of the density of states (DOS) effective mass md* from ∼3 m0 (300 K) to ∼7.5 m0 (1000 K), due to an improvement of the local symmetry of Ti O6 octahedra, enhancing the degeneracy in the Ti 3d orbitals, which form the conduction band (CB), and also to an accompanying lattice expansion, which gives rise to a higher DOS at the bottom of the CB and, consequently, a larger md*.

UR - http://www.scopus.com/inward/record.url?scp=37149025652&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=37149025652&partnerID=8YFLogxK

U2 - 10.1063/1.2820447

DO - 10.1063/1.2820447

M3 - Article

AN - SCOPUS:37149025652

VL - 91

JO - Applied Physics Letters

JF - Applied Physics Letters

SN - 0003-6951

IS - 24

M1 - 242102

ER -