Superconducting ground state of quasi-one-dimensionalK2Cr3As3investigated usingμSRmeasurements

Ferromagnetic Spin Fluctuation and Unconventional Superconductivity inRb2Cr3As3Revealed byYang1, Tang2, Cao3 et al. 2015Phys. Rev. Lett.

“…Nuclear quadrupole resonance (NQR) measurement in K 2 Cr 3 As 3 found no coherence (Hebel-Slichter) peak in the temperature (T ) dependence of the spin lattice relaxation rate (1/T 1 ) just below T c [15]. These results suggest unconventional superconductivity, which was echoed by other subsequent measurements [16,17]. Theoretically, ferromagnetic spin fluctuations due to Cr-Cr direct interaction were suggested in view of the calculated electronic band structure and the peculiar crystal structure [9,18], and unconventional pairing states have been proposed [10,19].…”

Coupling of structure to magnetic and superconducting orders in quasi-one-dimensional K2Cr3As3

“…nFL behaviors are observed in transport, nuclear magnetic resonance (NMR) and muon spectroscopy (µSR) measurements, which indicate significant electron correlations and strong magnetic fluctuations [11][12][13] . More exotically, measurements of the penetration depth find nodes in the superconducting gap while those of the upper critical field (H c2 ) find H c2 to be highly anisotropic, greatly exceed the Pauli-pair-breaking limit, exhibit an in-plane angular dependence and even a possible FuldeFeerel-Larkin-Ovchinnikov (FFLO) state [14][15][16] .…”

Multiband One-Dimensional Electronic Structure and Spectroscopic Signature of Tomonaga-Luttinger Liquid Behavior in K2Cr3AsWatson1, Feng2, Nicholson3 et al. 2017Phys. Rev. Lett.Self Cite593410View full textAdd to dashboardCite

“…The inclusion of Cr in the structure is a rare example of incorporating 3d orbitals into a Q1D system, as opposed to the well-known case of 4d orbitals in metallic Mo-based Q1D systems Li 0.9 Mo 6 O 17 and Tl 2 Mo 6 Se 6 , which brings the possibility of strong correlations [1] and magnetic interactions, which may be frustrated due to the triangular Cr motifs in the structure [3]. Superconductivity is found at 6.1 K in K 2 Cr 3 As 3 [4], which ranks amongst the highest T c for Q1D systems, and has been suggested to be of an unconventional nature [1] with some experimental [5,6] and theoretical [7][8][9] support for a triplet pairing state. Finally, the one dimensionality of the system makes it a candidate for Tomonaga-Luttinger liquid (TLL) physics [7,[10][11][12].…”