Coexistence of Dirac fermion and charge density wave in the square-net-based semimetal ${\mathrm{LaAuSb}}_{2}$

Coexistence of Dirac fermion and charge density wave in the square-net-based semimetal ${LaAuSb}_{2}$

Xueliang Wu, Zhixiang Hu, David Graf, Yu Liu, Chaoyue Deng, Huixia Fu, Asish K. Kundu, Tonica Valla, Cedomir Petrovic, and Aifeng Wang

Phys. Rev. B 108, 245156 – Published 27 December 2023

Abstract

We report a comprehensive study of magnetotransport properties, angle-resolved photoemission spectroscopy (ARPES), and density functional theory (DFT) calculations on self-flux grown ${LaAuSb}_{2}$ single crystals. Resistivity and Hall measurements reveal a charge density wave (CDW) transition at 77 K. MR and de Haas-van Alphen measurements indicate that the transport properties of ${LaAuSb}_{2}$ are dominated by Dirac fermions that arise from Sb square nets. ARPES measurements and DFT calculations reveal an electronic structure with a common feature of the square-net-based topological semimetals, which is in good agreement with the magnetotransport properties. Our results indicate the coexistence of CDW and Dirac fermion in ${LaAuSb}_{2}$ , both of which are linked to the bands arising from the Sb square net, suggesting that the square net could serve as a structural motif to explore various electronic orders.

Received 7 June 2023
Revised 20 November 2023
Accepted 8 December 2023

DOI:https://doi.org/10.1103/PhysRevB.108.245156

Physics Subject Headings (PhySH)

Charge density waves Fermi surface

Topological materials

Angle-resolved photoemission spectroscopy Crystal growth Density functional theory Transport techniques de Haas-van Alphen effect

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Xueliang Wu^1,*, Zhixiang Hu^2,3,*, David Graf⁴, Yu Liu ^2,5, Chaoyue Deng⁶, Huixia Fu⁶, Asish K. Kundu², Tonica Valla ⁷, Cedomir Petrovic^2,3,8,9,†, and Aifeng Wang ^1,2,‡

¹Low Temperature Physics Laboratory, College of Physics and Center of Quantum Materials and Devices, Chongqing University, Chongqing 401331, China
²Condensed Matter Physics and Materials Science Department, Brookhaven National Laboratory, Upton, New York 11973, USA
³Department of Material Science and Chemical Engineering, Stony Brook University, Stony Brook, New York 11790, USA
⁴National High Magnetic Field Laboratory, Florida State University, Tallahassee, Florida 32306-4005, USA
⁵Center for Correlated Matter and School of Physics, Zhejiang University, Hangzhou 310058, China
⁶College of Physics and Center of Quantum Materials and Devices, Chongqing University, Chongqing 401331, China
⁷Donostia International Physics Center, Donostia - San Sebastián, 20018, Spain
⁸Shanghai Advanced Research in Physical Sciences, Shanghai 201203, China
⁹Department of Nuclear and Plasma Physics, Vinca Institute of Nuclear Sciences, University of Belgrade, Belgrade 11001, Serbia

^*These authors contributed equally to this work.
^†[email protected]
^‡[email protected]

Article Text (Subscription Required)

Click to Expand

Supplemental Material (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand

Issue

Vol. 108, Iss. 24 — 15 December 2023

Reuse & Permissions

Access Options

Article part of CHORUS

Accepted manuscript will be available starting 26 December 2024.

Author publication services for translation and copyediting assistance advertisement

Images

Figure 1
(a) The crystal structure of ${LaAuSb}_{2}$ . Sb1 and Sb2 denote the Sb located in the Sb square net and anti-PbO type AuSb layer, respectively (b) Refined powder x-ray diffraction (PXRD) pattern for ${LaAuSb}_{2}$ . Weak peaks corresponding to a small amount of residual Sb flux were observed in the PXRD pattern. (c) Core-level electronic structure of ${LaAuSb}_{2}$ , measured using a photon energy of 150 eV. (d) Temperature dependence of in-plane resistivity $ρ_{x x}$ ( $j ∥ a b$ ) at 0 and 9 T and out-of-plane resistivity $ρ_{z z}$ ( $j ∥ c$ ) at 0 T for a ${LaAuSb}_{2}$ single crystal, where $j$ is the electric current applied for the resistivity measurements. (e) Temperature dependence of specific heat for ${LaAuSb}_{2}$ . The inset shows the enlarged view around $T_{CDW}$ . The red line represents the fit using the Debye-Einstein model.
Reuse & Permissions
Figure 2
(a) Magnetic field dependence of MR at various temperatures with $B ∥ c$ . (b) Log-log plot of the MR versus $B$ curves. (c) Temperature dependence of the exponent $n$ in MR = $A B^{m}$ . (d) Kohler plot on log-log scale for ${LaAuSb}_{2}$ . (e) Hall resistivity $ρ_{y x}$ as a function of the magnetic field at different temperatures with $B ∥ c$ . Each subsequent $ρ_{y x} (B)$ curve is shifted upward $0.5 \times 10^{- 1} μ Ω$ cm for clarity. The fits using the two-band approach are shown by red lines. (f) Temperature dependence of carrier concentration and mobility, which is estimated by the single-band fitting for $T > T_{CDW}$ and the two-band fitting for $T < T_{CDW}$ . (a), (b), (d), and (e) use the same legend.
Reuse & Permissions
Figure 3
(a) Isothermal out-of-plane magnetization $[M (B)]$ for ${LaAuSb}_{2}$ at various temperatures from 2–50 K. (b) The oscillatory component of magnetization, $Δ M$ . (c) The FFT spectra for the oscillatory component ( $Δ M$ ) for $B ∥ c$ . (d) Temperature dependence of the FFT amplitude of the main frequencies, which is obtained from the FFT spectra for $Δ τ$ in (g). Solid lines represent the fits of the LK formula. (e) The field dependence of magnetic torque $τ$ for $LaAu {Sb}_{2}$ at different temperatures. The inset is the enlarged view of the high-field part of $τ$ as indicated by the black rectangle, where the high-frequency oscillation can be visualized. (f) The oscillatory component of $τ$ for $B ∥ c$ . The inset displays a high-frequency oscillatory component obtained by filtering out low-frequency oscillations. (g) FFT spectra for the dHvA oscillation in the magnetic field range of 8 T $< B <$ 35 T. The dashed lines represent the FFT spectra for the dHvA oscillation in the magnetic field range of 25 T $< B <$ 35 T, which are magnified ten times in magnitude for clarity. (h) LL index fan diagram for oscillation component $Δ M$ at 2 K and $Δ τ$ at 0.5 K, where the Berry phase extracted from $Δ M$ is in good agreement with $Δ τ$ . The black line represents a linear fit to all LL indices, which yields an intercept of $n_{0} =$ 0.9.
Reuse & Permissions
Figure 4
(a) dHvA oscillations ( $Δ τ$ ) at $T$ = 0.5 K for different magnetic field orientations. The FFT spectra of the $Δ τ$ in the magnetic field range of 8 T $< B <$ 35 T and 25 T $< B <$ 35 T are displayed in (b) and (c), respectively. Data at different field orientations have been shifted for clarity. The dash lines are guides for the eye. (d) The angular dependence of $F_{α}$ , the solid lines are the fits to $F = F_{2 D} / \cos θ$ . (a)–(c) use the same legend.
Reuse & Permissions
Figure 5
Electronic structure of ${LaAuSb}_{2}$ from ARPES. (a) The Fermi surface. (b)–(e) ARPES spectra along the high-symmetry lines of the surface Brillouin zone, as indicated. Spectra in (a)–(e) were taken using a photon energy of 95 eV, near the $π / c$ plane of the 3D BZ at $T$ = 15 K. (f) The Fermi surface in the out-of-plane direction, $k_{z}$ , at $k_{y} = 0$ , recorded at photon energies in the range from 76–120 eV.
Reuse & Permissions
Figure 6
Calculated band structures of ${LaAuSb}_{2}$ without (a) and with (b) spin-orbit coupling at $k_{z}$ = 0. Calculated band structures of ${LaAuSb}_{2}$ without (c) and with (d) spin-orbit coupling at $k_{z}$ = $π / c$ . Red, green, and blue circles represent the contribution from Au, Sb1, and Sb2 orbitals. The area of the circles represents the relative weight of the orbitals. (e) Three-dimensional (3D) Brillouin zone of ${LaAuSb}_{2}$ . (f) 3D Fermi surface of ${LaAuSb}_{2}$ at $E = - 0.01$ eV, which consists of four Fermi pockets plotted separately in (g)–(j) for clarity.
Reuse & Permissions

Physical Review B

covering condensed matter and materials physics

Coexistence of Dirac fermion and charge density wave in the square-net-based semimetal ${LaAuSb}_{2}$

Xueliang Wu, Zhixiang Hu, David Graf, Yu Liu, Chaoyue Deng, Huixia Fu, Asish K. Kundu, Tonica Valla, Cedomir Petrovic, and Aifeng Wang

Phys. Rev. B 108, 245156 – Published 27 December 2023

Abstract

Physics Subject Headings (PhySH)

Authors & Affiliations

Article Text (Subscription Required)

Supplemental Material (Subscription Required)

References (Subscription Required)

Issue

Access Options

Physical Review B

covering condensed matter and materials physics

Coexistence of Dirac fermion and charge density wave in the square-net-based semimetal LaAuSb2

Xueliang Wu, Zhixiang Hu, David Graf, Yu Liu, Chaoyue Deng, Huixia Fu, Asish K. Kundu, Tonica Valla, Cedomir Petrovic, and Aifeng Wang

Phys. Rev. B 108, 245156 – Published 27 December 2023

Abstract

Physics Subject Headings (PhySH)

Authors & Affiliations

Article Text (Subscription Required)

Supplemental Material (Subscription Required)

References (Subscription Required)

Issue

Access Options

Authorization Required

Other Options

Download & Share

Images

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Log In

Search

Article Lookup

Paste a citation or DOI

Enter a citation

Coexistence of Dirac fermion and charge density wave in the square-net-based semimetal ${LaAuSb}_{2}$