Coexistence of Magnetism and Superconductivity in Hybrid Ruthenocuprates

该个人研究者奖支持一个项目，其目标是通过测量极端磁场和压力条件下的输运、磁性和热性能，进一步了解钌-铜酸盐混合磁性超导体Ru-1212和Ru-1222。这些材料的晶体结构来源于高Tc超导体YBa(2) cu30 (7-x) （Tc接近90k）的结构。这些钌铜酸盐的一个独特特征是在45 K以下的超导状态与在较高温度下建立的弱铁磁性共存。虽然从晶体学的角度来看，这些层状材料是准二维的，但磁性和超导顺序都是三维的，这表明Ru-O磁性层通过Cu-O层耦合，而超导Cu-O层通过Ru-O磁性层耦合。这些实验将使人们更好地了解这些有趣的磁性超导体。该项目将为该机构的本科生和硕士生创造独特的研究、教育和指导机会。该项目的目标是通过在非常高的磁场和压力下测量电、磁和热性能，对钌-铜酸盐混合磁性超导体进行实验研究。这些材料在结构上类似于高温超导体YBa(2) cu30 (7-x)，在90k以下表现为零电阻。这些钌-铜酸盐的一个真正有趣的特征是，磁性有序与45 K以下的超导性共存。虽然这两种现象的共存是非常罕见的，但在过去，对这类材料的研究已经导致了许多重要的发现。由于钌-铜酸盐是层状材料，可以想象超导性和磁性有序共存的原因是超导Cu-O层与磁性Ru-O层之间的耦合较弱。提出的实验将使人们更好地了解这些非常不寻常的磁性超导体。该项目将为该机构的本科生和硕士生创造独特的研究、教育和指导机会。

This individual investigator award supports a project with the goal of gaining an increased understanding of the hybrid rutheno-cuprates magnetic superconductors known as Ru-1212 and Ru-1222, by means of measurements of transport, magnetic, and thermal properties in extreme conditions of magnetic field and pressure. The crystal structure of these materials is derived from the structure of the high-Tc superconductor YBa(2)Cu3O(7-x) (Tc near 90 K). A unique feature of these rutheno-cuprates is that the superconducting state below 45 K coexists with the weak ferromagnetism established at higher temperatures. Although these layered materials are quasi-two-dimensional from a crystallography point of view, both the magnetic and superconducting orders are three-dimensional, which suggests that the Ru-O magnetic layers couple through the Cu-O layers, while the superconducting Cu-O layers couple through the Ru-O magnetic layers. These experiments will permit a better understanding of these intriguing magnetic superconductors. This project will create unique research, educational, and mentoring opportunities for the undergraduate and Masters degree students at this institution.The goal of this project is to carry out an experimental study of the hybrid rutheno-cuprates magnetic superconductors, by means of measurements of electrical, magnetic, and thermal properties in very high magnetic fields and pressures. These materials are structurally similar to the high-temperature superconductor YBa(2)Cu3O(7-x), which shows zero electrical resistance below 90 K. A truly intriguing feature of these rutheno-cuprates is that the magnetic order coexists with superconductivity below 45 K. Although coexistence of these two phenomena is very rare, studies of such materials have lead to many important findings in the past. Since the rutheno-cuprates are layered materials, it is conceivable that the reason superconductivity and magnetic order coexist is that the coupling between the superconducting Cu-O layers and the magnetic Ru-O layers is weak. The experiments proposed will permit a better understanding of these quite unusual magnetic superconductors. This project will create unique research, educational, and mentoring opportunities for the undergraduate and Masters degree students at this institution.