Investigations of Unconventional Superconducting and Magnetic Order-Parameters in Heavy Electron Materials

9624468希瓦拉姆将研究一类新的由稀土和氡系元素形成的金属间化合物的超导和磁性。在这些材料中，低温行为是由电子之间的相互作用所主导的。将使用一些先进的仪器和技术，如超声波、超导量子干涉装置以及扫描磁力测量和传输测量。测量将在高质量的单晶和薄膜样品上进行。极端的物理条件，如高单轴压力、强磁场和极低温度，将被适当地选择，以阐明这些材料中超导和磁性的独特性质。为此，将使用一种特殊的低温设备，其中单轴压力高达8000大气压，磁场强度接近地球磁场的一百万倍。所获得的结果将与材料科学的许多领域有关，包括高温超导、磁存储、高场磁材料等。将用超声波、力、SQUID磁测量(宏观和微观)和输运测量来研究稀土金属间重费米子化合物的超导和磁相。这些测量将在高质量的单晶和薄膜样品上进行。为了阐明这些材料中的新的超导和磁性现象，将适当地选择一系列涉及高单轴压力、强磁场和超低温的实验。这些现象包括(I)超导与磁的共存，(Ii)超导状态下的多序参数，(i，ii)具有半量子循环的磁场涡旋，(Iv)具有非Neel有序类型的磁性，以及(V)由于界面的存在而产生的新的磁效应和输运效应。测量将利用一种特殊的超低温仪器，其中外部施加的扰动的大小和相互方向可以现场控制，单轴压力高达8千巴，磁场高达16特斯拉。***

9624468 Shivaram The superconducting and magnetic properties of a new class of intermetallic compounds formed from rare earth and actinide elements will be investigated. In these materials, the low temperature behavior is dominated by the interactions between the electrons. A number of advanced instrumentation and techniques such as ultrasonics, superconducting quantum interference devices as well as scanning magnetometry, and transport measurements will be used. The measurements will be performed on high quality single crystals as well as on thin film samples. Extreme physical conditions such as high uniaxial pressures, high magnetic fields and very low temperatures will be chosen as appropriate to elucidate the unique nature of superconductivity and magnetism in these materials. For this purpose a special low temperature apparatus where uniaxial pressure up to 8,000 atmosphere and magnetic fields close to a million times stronger than the earth's magnetic filed, will be utilized. The results obtained will be relevant to many areas in materials science including high temperature superconductivity, magnetic storage, high field magnetic materials etc. %%% The superconducting and magnetic phases of rare earth and actinide based intermetallic heavy fermion compounds will be investigated with ultrasonics, force as well as SQUID magnetometry (both macroscopic and microscopic) and transport measurements. These measurements will be performed on high quality single crystals as well as on thin film samples. A combination of experiments involving high uniaxial pressures, high magnetic fields and ultra-low temperatures will be chosen as appropriate to elucidate the novel superconducting and magnetic phenomena in these materials. These phenomena include (i) coexistence of superconductivity and magnetism, (ii) multiple order parameters in the superconducting state, (i ii) magnetic filed vortices with half a quantum of circulation, (iv) magnetism with non-Neel types of order, and (v) novel magnetic and transport effects due to the presence of interfaces. The measurements will utilize a special ultra low temperature apparatus where the magnitude and the mutual orientations of externally applied perturbations, uniaxial pressures upto 8 kbar and magnetic fields upto 16 tesla, can be controlled in situ. ***