Proposal for Detecting Nodal-Line Semimetal Surface States with Resonant Spin-Flipped Reflection

Abstract

Topological nodal-line semimetals are predicted to exhibit unique drumhead-like surface states (DSS). Yet, a direct detection of such states remains a challenge. Here, we propose spin-resolved transport in a junction between a normal metal and a spin-orbit coupled nodal-line semimetal as the mechanism for their detection. Specifically, we find that in such an interface, the DSS induce resonant spin-flipped reflection. This effect can be probed by both vertical spin transport and lateral charge transport between anti-parallel magnetic terminals. In the tunneling limit of the junction, both spin and charge conductances exhibit a resonant peak around zero energy, providing a unique evidence of the DSS. This signature is robust to both dispersive-DSS and interface disorder. Based on numerical calculations, we show that the scheme can be implemented in the topological semimetal HgCr2Se4.

Accurate magneto-optical determination of radius of topological nodal-ring semimetals

“…Owing to their potential applications, many theoretical models for realizing TNRSMs have been proposed [9,12]. The properties of TNRSMs have been investigated, such as the magnetic susceptibility [15], the quantum oscillations [16][17][18][19][20][21], the Landau quantization [22,23], the quantum anomalies [24], the Lifshitz transitions [25], and other transport properties [26][27][28][29][30][31][32][33][34] . Electronic correlations and superconductivity have also been studied [35][36][37][38][39][40][41].…”

Floquet-engineering of nodal rings and nodal spheres and their characterization using the quantum metric

“…While the former class includes topological insulators and superconductors, but also quantum Hall states [5][6][7], the latter class concerns topological semimetals (e.g. Weyl, Dirac and nodal-line semimetals), which have been intensively investigated in the recent years [8][9][10][11][12][13][14][15][16][17][18]; besides, topological phases with nodal surfaces have also been theoretically proposed [19][20][21][22][23]. These gapless systems can display remarkable properties, such as Fermi arcs or drumhead surface states on the boundaries, and momentum-space Dirac monopoles in the bulk.…”

Signature of odd-frequency equal-spin triplet pairing in the Josephson current on the surface of Weyl nodal loop semimetals

“…The Hamiltonian for a minimal model of a 3D WNLS breaking time-reversal symmetry is 6,7,10 where k i is the wave vector along the i-th (x, y or z) axis and the Pauli matrices, σ i act in spin space. The first two terms give rise to a Fermi nodal loop with its shape set by α 1 and α 2 and protected by T I-symmetry, a product of time-reversal (T ) and inversion (I) symmetry, and mirror symmetry with respect to k z →−k z 4 .…”