Title: Putative hybridization gap in ${\mathrm{CaMn}}_2{\mathrm{Bi}}_2$ under applied pressure

Abstract

Here, we study electrical transport measurements on ${\mathrm{CaMn}}_2{\mathrm{Bi}}_2$ single crystals under applied pressure. At ambient pressure and high temperatures, ${\mathrm{CaMn}}_2{\mathrm{Bi}}_2$ behaves as a single-band semimetal hosting Néel order at T_N = 150 K. At low temperatures, multiband behavior emerges along with an activated behavior typical of degenerate semiconductors. The activation gap is estimated to be Δ~ 20 K. Applied pressure not only favors the antiferromagnetic order at a rate of 0.40(2) K/kbar, but it also enhances the activation gap at 20 kbar by about 70%. This gap enhancement is usual of correlated narrow-gap semiconductors such as FeSi and Ce₃Bi₄Pt₃, and it places ${\mathrm{CaMn}}_2{\mathrm{Bi}}_2$ as a Mn-based hybridization-gap semiconductor candidate. Ab initio calculations based on density functional theory are demonstrated to be insufficient to describe the ground state of ${\mathrm{CaMn}}_2{\mathrm{Bi}}_2$.

Authors:

Moda Piva, Mario  ^[1];

• Search DOE PAGES for author "Moda Piva, Mario"
• Search DOE PAGES for ORCID "0000-0003-4744-3397"

Thomas, Sean Michael  ^[2];

• Search DOE PAGES for author "Thomas, Sean Michael"
• Search DOE PAGES for ORCID "0000-0003-0889-4435"

Fisk, Zachary ^[3]; Zhu, J. -X. ^[2]; Thompson, Joe David  ^[2];

• Search DOE PAGES for author "Thompson, Joe David"
• Search DOE PAGES for ORCID "0000-0001-8801-157X"

Pagliuso, P. G. ^[4]; Ferrari Silveira Rosa, Priscila  ^[2]

• Search DOE PAGES for author "Ferrari Silveira Rosa, Priscila"
• Search DOE PAGES for ORCID "0000-0002-3437-548X"

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+ Show Author Affiliations

1. Univ. of Campinas (UNICAMP), Sao Paulo (Brazil); Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
2. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
3. Univ. of California, Irvine, CA (United States)
4. Univ. of Campinas (UNICAMP), Sao Paulo (Brazil)

Publication Date:

Mon Jul 08 00:00:00 EDT 2019

Research Org.:

Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22). Materials Sciences & Engineering Division; USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1561083

Alternate Identifier(s):

OSTI ID: 1546428

Report Number(s):

LA-UR-19-28476
Journal ID: ISSN 2469-9950; PRBMDO; TRN: US2000588

Grant/Contract Number:  

89233218CNA000001

Resource Type:

Accepted Manuscript

Journal Name:

Physical Review B

Additional Journal Information:

Journal Volume: 100; Journal Issue: 4; Journal ID: ISSN 2469-9950

Publisher:

American Physical Society (APS)

Country of Publication:

United States

Language:

English

Subject:

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY