Dirac semimetal PdTe2 temperature-dependent quasiparticle dynamics and electron-phonon coupling

Abstract

Dirac semimetal PdTe2 single-crystal temperature-dependent ultrafast carrier and phonon dynamics were studied using ultrafast optical pump-probe spectroscopy. Two distinct carrier and coherent phonons relaxation processes were identified in the 5 K - 300 K range. Quantitative analysis revealed a fast relaxation process (τ_f) occurring on a subpicosecond time scale which originated from electron-phonon thermalization. This was followed by a slower relaxation process (τ_s) with a time scale of ~ 7-9.5 ps which originated from phonon-assisted electron-hole recombination. Two significant vibrational modes resolved at all measured temperatures and corresponded to Te atoms in-plane (E_g), and out-of-plane (A_1g), motion. As temperature increased both phonon modes softened markedly. A_1g mode frequency monotonically decreased as temperature increased. Its damping rate remained virtually unchanged. As expected, E_g decreased uniformly as temperatures rose. At temperatures above 80 K, there was insignificant change. Test results suggested that pure dephasing played an important role in the relaxation processes. PdTe2 phonon is thought responsible for its superconductive properties. Examining phonons behavior should improve the understanding of its complex superconductivity.

arXiv comment6 pages, 4 figures

References in corpus (21)

• Topological Insulators
• Topological insulators and superconductors
• Titanic Magnetoresistance in WTe2
• Topological superconductors: a review
• Lorentz-violating type-II Dirac fermions in transition metal dichalcogenide PtTe${}_2$
• Experimental Realization of Type-II Dirac Fermions in PdTe${}_2$ Superconductor
• Topological superconductivity in monolayer transition metal dichalcogenides
• Nontrivial Berry phase and type II Dirac transport in layered material PdTe2
• Ubiquitous formation of bulk Dirac cones and topological surface states from a single orbital manifold in transition-metal dichalcogenides
• Fermiology and Superconductivity of Topological Surface States in PdTe${}_2$
• Dynamics of photoinduced Charge Density Wave-metal phase transition in K0.3MoO3
• Emergence of charge density waves and a pseudogap in single-layer TiTe2
• Inversion-protected higher order topological superconductivity in monolayer WTe${}_2$
• Type I superconductivity in the Dirac semimetal PdTe2
• Nodeless superconductivity in type-II Dirac semimetal PdTe2: low-temperature London penetration depth and symmetry analysis
• Type-I superconductivity in PdTe${}_2$ probed by $\mu$SR
• Composition-induced structural instability and strong-coupling superconductivity in Au1-xPdxTe2
• Measurement of Two Low-Temperature Energy Gaps in the Electronic Structure of Antiferromagnetic USb2 Using Ultrafast Optical Spectroscopy
• Coupling Between An Optical Phonon and the Kondo Effect
• Electronic transport properties of intermediately coupled superconductors: PdTe2 and Cu0.04PdTe2
• Single full gap with mixed type-I and type-II superconductivity on surface of the type-II Dirac semimetal PdTe2 by point-contact spectroscopy

Cited by in corpus (10)

• Ultrafast Optical Spectroscopy Evidence of Pseudogap and Electron-Phonon Coupling in an Iron-Based Superconductor KCa${}_2$Fe${}_4$As${}_4$F${}_2$
• Charge Density Wave order and electron-phonon coupling in ternary superconductor Bi${}_2$Rh${}_3$Se${}_2$
• Angle-resolved photoemission spectroscopy study of the charge density wave order in layered semiconductor EuTe4
• Investigation of structural and magneto-transport properties of PdTe2 single crystals
• Coupling of optical phonons with Kondo effect and magnetic orders in antiferromagnetic Kondo lattice CeAuSb${}_2$
• The Hidden Nematic Fluctuations in the Triclinic (Ca0.85La0.15)10(Pt3As8)(Fe2As2)5 Superconductor Revealed by Ultrafast Optical Spectroscopy
• Multiple charge-density-wave gaps in LaSbTe and CeSbTe as revealed by ultrafast spectroscopy
• Nonequilibrium carrier and phonon dynamics in the ferrimagnetic semiconductor Mn${}_3$Si${}_2$Te${}_6$
• Research on topological materials using ultrafast spectroscopy
• Ultrafast Carrier Relaxation and Second Harmonic Generation in a Higher-Fold Weyl Fermionic System PtAl