Anomalous hyperfine coupling and nuclear magnetic relaxation in Weyl semimetals

Abstract

The electron-nuclear hyperfine interaction shows up in a variety of phenomena including e.g. NMR studies of correlated states and spin decoherence effects in quantum dots. Here we focus on the hyperfine coupling and the NMR spin relaxation time, $T_1$ in Weyl semimetals. Since the density of states in Weyl semimetals varies with the square of the energy around the Weyl point, a naive power counting predicts a $1/T_{1}T\sim E^4$ scaling with $E$ the maximum of temperature ($T$) and chemical potential. By carefully investigating the hyperfine interaction between nuclear spins and Weyl fermions, we find that while its spin part behaves conventionally, its orbital part diverges unusually with the inverse of energy around the Weyl point. Consequently, the nuclear spin relaxation rate scales in a graphene like manner as $1/T_{1}T\sim E^2\ln (E/{\omega }_0)$ with ${\omega }_0$ the nuclear Larmor frequency. This allows us to identify an effective hyperfine coupling constant, which is tunable by gating or doping, which is relevant for decoherence effect in spintronics devices and double quantum dots where hyperfine coupling is the dominant source of spin-blockade lifting.

arXiv comment7 pages, 2 figures

References in corpus (19)

• The electronic properties of graphene
• Topological Insulators
• Topological insulators and superconductors
• Spintronics: Fundamentals and applications
• Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
• Quantum Spin Hall Insulator State in HgTe Quantum Wells
• Electronic Structure of Pyrochlore Iridates: From Topological Dirac Metal to Mott Insulator
• Discovery of a Weyl Fermion Semimetal and Topological Fermi Arcs
• Weyl Semimetal in a Topological Insulator Multilayer
• Theoretical Discovery/Prediction: Weyl Semimetal states in the TaAs material (TaAs, NbAs, NbP, TaP) class
• Observation of the chiral anomaly induced negative magneto-resistance in 3D Weyl semi-metal TaAs
• Observation of a topological 3D Dirac semimetal phase in high-mobility Cd3As2
• Phase transition between the quantum spin Hall and insulator phases in 3D: emergence of a topological gapless phase
• Experimental observation of Weyl points
• Signatures of the Adler-Bell-Jackiw chiral anomaly in a Weyl Fermion semimetal
• Electron Transport in Double Quantum Dot governed by Nuclear Magnetic Field
• Magnetic susceptibility in three-dimensional nodal semimetals
• Hyperfine interactions in two-dimensional HgTe topological insulators
• Unusual hyperfine interaction of Dirac electrons and NMR spectroscopy in graphene

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• Exotic Landau Diamagnetism and Weyl-Fermions Excitations in TaAs Revealed by ${}^{75}$As NMR and NQR
• Nuclear spin-lattice relaxation time in TaP and the Knight shift of Weyl semimetals
• S-wave Superconductivity in the Dirac Line-nodal Material CaSb2
• Nuclear Spin Relaxation Time due to the Orbital Currents in Dirac Electron Systems
• Local Observations of Orbital Diamagnetism and Excitation in Three-Dimensional Dirac Fermion Systems Bi${}_{1-x}$Sb${}_x$
• Site-dependent Local Spin Susceptibility and Low-energy Excitation in a Weyl Semimetal WTe${}_2$
• Nuclear spin relaxation rate near the disorder-driven quantum critical point in Weyl fermion systems
• Anisotropic superconductivity in the quasi-one-dimensional superconductor V${}_2$Ga${}_5$
• Experimental nuclear quadrupole resonance and computational study of the structurally refined topological semimetal TaSb${}_2$
• Fast nuclear spin relaxation rates in tilted cone Weyl semimetals: Redshift factors from Korringa relation
• Comparative ${}^{181}$Ta-NQR Study of Weyl Monopnictides TaAs and TaP: Relevance of Weyl Fermion Excitations
• Magnetic-field-induced electronic instability of Weyl-like fermions in compressed black phosphorus
• ${}^{27}$Al NMR study of the magnetic Weyl semimetal CeAlGe
• 125Te spin-lattice relaxation in a candidate to Weyl semimetals WTe2