Intrachain collinear magnetism and interchain magnetic phases in Cr3As3−K -based materials

Abstract

We perform a comparative study of the KCr3As3 and the K2Cr3As3 quasi 1D compounds, and show that the strong interplay between the lattice and the spin degrees of freedom promotes a new collinear ferrimagnetic ground state within the chains in presence of intrachain antiferromagnetic couplings. We propose that the interchain antiferromagnetic coupling in KCr3As3 plays a crucial role for the experimentally observed spin-glass phase with low critical temperature. In the same region of the parameter space, we predict K2Cr3As3 to be non-magnetic but on the verge of the magnetism, sustaining interchain ferromagnetic spin fluctuations while the intrachain spin fluctuations are antiferromagnetic.

Magnetic Instabilities in the Quasi-One-Dimensional K2Cr3As3 Material with Twisted Triangular Tubes

“…Interestingly, it has theoretically been reported that the jumps may occur just below saturation and should be observable in magnetization experiments if the coupling constants are small enough to make the saturating field accessible [ 33 ]. Therefore, as the lattice structure of the material here investigated contains twisted tubes triangularly arranged [ 22 , 23 ], we are confident that the jumps observed in our samples originate from the geometrical frustration of the crystal structure of K 2 Cr 3 As 3 . However, in our compound, we have an additional dynamical effect that makes the magnetic state after the jump energetically unstable.…”

“…This situation is not in contrast with a ferrimagnetic behavior, in agreement with the results reported in Refs. [ 22 , 23 ]. We point out that our measurements are bulk ones, so the results obtained are not due to surface effects.…”

“…These jumps in magnetization were calculated to be of the order of 0.003 Bohr magneton per Cr atom; therefore, they are relatively small compared to the magnetic moments that the Cr atoms can reach. Theoretical calculations [ 22 ] predict K 2 Cr 3 As 3 to be nonmagnetic but on the verge of magnetism, sustaining interchain ferromagnetic spin fluctuations while the intrachain spin fluctuations are antiferromagnetic. In this regime, the magnetic moment of the Cr ion is strongly suppressed compared to the bare Cr magnetic moment.…”

“…These distortions from the triangular structure make the system no longer frustrated. Very recently, we have shown that there is a strong interplay between the structural distortions and magnetism, and we have found that, for the distorted structure, a collinear intrachain ferrimagnetic ground state for the KCr 3 As 3 and an instability towards the same collinear intrachain ferrimagnetic phase for K 2 Cr 3 As 3 [ 22 , 23 ]. Assuming intrachain ferrimagnetism, the system could exhibit long-range ferrimagnetism or spin-glass phase depending on the interchain magnetic coupling.…”

Dimensionality of the Superconductivity in the Transition Metal Pnictide WP

“…Although many interesting studies have been so far reported on these and other similar compounds, both theoretical [12][13][14][15][16][17][18][19][20][21][22][23][24][25] and experimental [26][27][28][29][30][31][32][33][34][35][36], only a limited amount of information on WP single crystal system is until now available [8]. The aim of this paper is to give a contribution to the investigation of the properties of WP compound, providing electronic structure calculations and a consistent description of resistivity measurements from experiments carried out on WP single crystal samples.…”