2022 Vol. 1, No. 4
Phase-change materials that exploit phase transitions between the crystalline and amorphous states are a leading candidate for nonvolatile memory applications. This work reports a conductive-bridge phase-change scheme utilizing a self-decomposed alloy, which drastically reduces the programming energy to femtojoule-level. Specifically, incorporating suitable amount of oxygen into germanium antimonites leads to the formation of a heterogeneous network with intermixed germanium dioxide glass domains and antimony-rich crystalline domains, allowing the formation of a conductive path under external electrical stimulus. Hence, device programming can already be achieved by forming and breaking the nano-bridges, enabling low-power data storage.
The moderate on-site Coulomb repulsion U and SOC strength of Rh-4d electrons endow them with variable, intriguing natures, and this offers a rich platform for materials design. This work reports a new ternary rhodium-containing compound La2Rh3+δSb4 (δ≈1/8) that becomes a type-II superconductor at low temperature. The magic number δ ≈ 1/8 is reminiscent of the stripe phase observed in the high-Tc cuprates whose origin remains unclear. More importantly, this work also suggests that the broad family of Ln2Tm3+δSb4 (Ln = rare earth, Tm = transition metals)-whose physical properties are not yet well explored-likely hosts new quantum material bases where novel SC, quantum magnetism, quantum criticality and other electronic correlation effects can be found.