Existence of electron and hole pockets and partial gap opening in the correlated semimetal Ca 3 Ru 2 O 7

Hui Xing, Libin Wen, Chenyi Shen, Jiaming He, Xinxin Cai, Jin Peng, Shun Wang, Mingliang Tian, Zhu An Xu, Wei Ku, Zhiqiang Mao, Ying Liu

Research output: Contribution to journalArticle

3 Citations (Scopus)

Abstract

The electronic band structure of correlated Ca3Ru2O7 featuring an antiferromagnetic (AFM) as well as a structural transition has been determined theoretically at high temperatures, which has led to the understanding of the remarkable properties of Ca3Ru2O7, such as the bulk spin-valve effects. However, its band structure and Fermi surface (FS) below the structural transition have not been resolved, even though a FS consisting of electron pockets was found experimentally. Here we report magnetoelectrical transport and thermoelectric measurements with the electric current and temperature gradient directed along the a and b axes, respectively, of an untwined single crystal of Ca3Ru2O7. The thermopowers obtained along the two crystal axes were found to show opposite signs at low temperatures, demonstrating the presence of both electron and hole pockets on the FS. In addition, how the FS evolves across T∗=30K at which a distinct transition from coherent to incoherent behavior occurs was also inferred: the Hall and Nernst coefficient results suggest a temperature- and momentum-dependent partial gap opening in Ca3Ru2O7 below the structural transition with a possible Lifshitz transition occurring at T∗. The experimental demonstration of a correlated semimetal ground state in Ca3Ru2O7 calls for further theoretical studies of this remarkable material.

Original languageEnglish (US)
Article number041113
JournalPhysical Review B
Volume97
Issue number4
DOIs
StatePublished - Jan 19 2018

Fingerprint

Metalloids
Fermi surface
metalloids
Fermi surfaces
Electrons
Band structure
electrons
Electron tubes
Thermoelectric power
Electric currents
Electron transitions
Thermal gradients
Temperature
Ground state
Momentum
Demonstrations
electric current
Single crystals
Hall effect
temperature gradients

All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

Cite this

Xing, Hui ; Wen, Libin ; Shen, Chenyi ; He, Jiaming ; Cai, Xinxin ; Peng, Jin ; Wang, Shun ; Tian, Mingliang ; Xu, Zhu An ; Ku, Wei ; Mao, Zhiqiang ; Liu, Ying. / Existence of electron and hole pockets and partial gap opening in the correlated semimetal Ca 3 Ru 2 O 7. In: Physical Review B. 2018 ; Vol. 97, No. 4.
@article{8c4090a8b9b8478696231ce91524de34,
title = "Existence of electron and hole pockets and partial gap opening in the correlated semimetal Ca 3 Ru 2 O 7",
abstract = "The electronic band structure of correlated Ca3Ru2O7 featuring an antiferromagnetic (AFM) as well as a structural transition has been determined theoretically at high temperatures, which has led to the understanding of the remarkable properties of Ca3Ru2O7, such as the bulk spin-valve effects. However, its band structure and Fermi surface (FS) below the structural transition have not been resolved, even though a FS consisting of electron pockets was found experimentally. Here we report magnetoelectrical transport and thermoelectric measurements with the electric current and temperature gradient directed along the a and b axes, respectively, of an untwined single crystal of Ca3Ru2O7. The thermopowers obtained along the two crystal axes were found to show opposite signs at low temperatures, demonstrating the presence of both electron and hole pockets on the FS. In addition, how the FS evolves across T∗=30K at which a distinct transition from coherent to incoherent behavior occurs was also inferred: the Hall and Nernst coefficient results suggest a temperature- and momentum-dependent partial gap opening in Ca3Ru2O7 below the structural transition with a possible Lifshitz transition occurring at T∗. The experimental demonstration of a correlated semimetal ground state in Ca3Ru2O7 calls for further theoretical studies of this remarkable material.",
author = "Hui Xing and Libin Wen and Chenyi Shen and Jiaming He and Xinxin Cai and Jin Peng and Shun Wang and Mingliang Tian and Xu, {Zhu An} and Wei Ku and Zhiqiang Mao and Ying Liu",
year = "2018",
month = "1",
day = "19",
doi = "10.1103/PhysRevB.97.041113",
language = "English (US)",
volume = "97",
journal = "Physical Review B-Condensed Matter",
issn = "2469-9950",
publisher = "American Physical Society",
number = "4",

}

Existence of electron and hole pockets and partial gap opening in the correlated semimetal Ca 3 Ru 2 O 7. / Xing, Hui; Wen, Libin; Shen, Chenyi; He, Jiaming; Cai, Xinxin; Peng, Jin; Wang, Shun; Tian, Mingliang; Xu, Zhu An; Ku, Wei; Mao, Zhiqiang; Liu, Ying.

In: Physical Review B, Vol. 97, No. 4, 041113, 19.01.2018.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Existence of electron and hole pockets and partial gap opening in the correlated semimetal Ca 3 Ru 2 O 7

AU - Xing, Hui

AU - Wen, Libin

AU - Shen, Chenyi

AU - He, Jiaming

AU - Cai, Xinxin

AU - Peng, Jin

AU - Wang, Shun

AU - Tian, Mingliang

AU - Xu, Zhu An

AU - Ku, Wei

AU - Mao, Zhiqiang

AU - Liu, Ying

PY - 2018/1/19

Y1 - 2018/1/19

N2 - The electronic band structure of correlated Ca3Ru2O7 featuring an antiferromagnetic (AFM) as well as a structural transition has been determined theoretically at high temperatures, which has led to the understanding of the remarkable properties of Ca3Ru2O7, such as the bulk spin-valve effects. However, its band structure and Fermi surface (FS) below the structural transition have not been resolved, even though a FS consisting of electron pockets was found experimentally. Here we report magnetoelectrical transport and thermoelectric measurements with the electric current and temperature gradient directed along the a and b axes, respectively, of an untwined single crystal of Ca3Ru2O7. The thermopowers obtained along the two crystal axes were found to show opposite signs at low temperatures, demonstrating the presence of both electron and hole pockets on the FS. In addition, how the FS evolves across T∗=30K at which a distinct transition from coherent to incoherent behavior occurs was also inferred: the Hall and Nernst coefficient results suggest a temperature- and momentum-dependent partial gap opening in Ca3Ru2O7 below the structural transition with a possible Lifshitz transition occurring at T∗. The experimental demonstration of a correlated semimetal ground state in Ca3Ru2O7 calls for further theoretical studies of this remarkable material.

AB - The electronic band structure of correlated Ca3Ru2O7 featuring an antiferromagnetic (AFM) as well as a structural transition has been determined theoretically at high temperatures, which has led to the understanding of the remarkable properties of Ca3Ru2O7, such as the bulk spin-valve effects. However, its band structure and Fermi surface (FS) below the structural transition have not been resolved, even though a FS consisting of electron pockets was found experimentally. Here we report magnetoelectrical transport and thermoelectric measurements with the electric current and temperature gradient directed along the a and b axes, respectively, of an untwined single crystal of Ca3Ru2O7. The thermopowers obtained along the two crystal axes were found to show opposite signs at low temperatures, demonstrating the presence of both electron and hole pockets on the FS. In addition, how the FS evolves across T∗=30K at which a distinct transition from coherent to incoherent behavior occurs was also inferred: the Hall and Nernst coefficient results suggest a temperature- and momentum-dependent partial gap opening in Ca3Ru2O7 below the structural transition with a possible Lifshitz transition occurring at T∗. The experimental demonstration of a correlated semimetal ground state in Ca3Ru2O7 calls for further theoretical studies of this remarkable material.

UR - http://www.scopus.com/inward/record.url?scp=85040946060&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85040946060&partnerID=8YFLogxK

U2 - 10.1103/PhysRevB.97.041113

DO - 10.1103/PhysRevB.97.041113

M3 - Article

AN - SCOPUS:85040946060

VL - 97

JO - Physical Review B-Condensed Matter

JF - Physical Review B-Condensed Matter

SN - 2469-9950

IS - 4

M1 - 041113

ER -