Crystal Growth and Characterization of Centrosymmetric Magnets for Qubit Applications

A quantum bit, or qubit, is the core entity for quantum computing. Recently, theoreticians have proposed a new type of macroscopic qubits based on control of the helicity degree of freedom of magnetic skyrmions, topologically protected swirling spin textures. Here we report crystal growth of promising candidate materials for skyrmion qubits, centrosymmetric magnets that can host nanosized skyrmions. Single crystals of centrosymmetric magnets, Gd₃Ru₄Al₁₂, were grown by the Laser Diode Floating Zone (LDFZ) method. X-ray diffraction results have confirmed the single crystalline and high purity of the grown crystal samples. Temperature-dependent magnetic hysteresis loops and magneto-transport properties of these single-crystal samples have been investigated using a Quantum Design SQUID magnetometer and a Quantum Design PPMS, respectively. The humps and dips observed in the Hall resistance at low temperatures (2–10 K) are attributed to the topological Hall effect, offering strong evidence for the existence of a skyrmion phase.