Recently, new Cr-based superconductors, A2Cr3As3(A = K, Rb, Cs), have gained intense interest because of their one-dimensional crystal structures and electron correlations. Here we report the crystal structure and phy...Recently, new Cr-based superconductors, A2Cr3As3(A = K, Rb, Cs), have gained intense interest because of their one-dimensional crystal structures and electron correlations. Here we report the crystal structure and physical properties of two related materials ACr3As3(A = Rb, Cs) which are synthesized via a soft-chemical A+ deintercalation in A2Cr3As3. The new compounds remain one-dimensional(Cr3As3)∞ linear chains, and the interchain distance can be tuned by the incorporation of the alkali-metal cations with different sizes. The physical property measurements indicate a local-moment behavior at high temperatures, and the moments freeze into a cluster spin-glass state below 5–6 K. No superconductivity was observed in both materials. We also found that, with increasing the interchain distance, the Cr effective moments increase monotonically, accompanied with the enhancement of semi-conductivity. Our results shed light on the understanding of occurrence of superconductivity in A2Cr3As3.展开更多
基金supported by the National Natural Science Foundation of China (11190023 and 11474252)the National Basic Research Program (2011CBA00103)
文摘Recently, new Cr-based superconductors, A2Cr3As3(A = K, Rb, Cs), have gained intense interest because of their one-dimensional crystal structures and electron correlations. Here we report the crystal structure and physical properties of two related materials ACr3As3(A = Rb, Cs) which are synthesized via a soft-chemical A+ deintercalation in A2Cr3As3. The new compounds remain one-dimensional(Cr3As3)∞ linear chains, and the interchain distance can be tuned by the incorporation of the alkali-metal cations with different sizes. The physical property measurements indicate a local-moment behavior at high temperatures, and the moments freeze into a cluster spin-glass state below 5–6 K. No superconductivity was observed in both materials. We also found that, with increasing the interchain distance, the Cr effective moments increase monotonically, accompanied with the enhancement of semi-conductivity. Our results shed light on the understanding of occurrence of superconductivity in A2Cr3As3.
