Nanoscale study of complex oxide & intemetallic materials

在过去的几十年里，在复杂的氧化物和金属间材料中发现了大量新的电子有序现象。这些现象的范围从非常规的超导性和巨大的磁阻到磁电多铁性。纳米制造和纳米探针技术的最新进展，以及低温磁仪器的进步，使这些材料能够在非常短的长度尺度上，在极端的热力学条件下进行可控几何形状的研究。我建议的研究是将纳米制造、纳米探针和低温磁技术结合应用于各种复杂的氧化物和新型金属间化合物。材料包括：高tc超导体YBa2Cu3O6+x和掺杂tl的铜酸盐；重费米子超导体CeCoIn5、PrOs4Sb12、CePt3Si；巨磁阻（CMR）化合物La0.7Ca0.3MnO3；以及多铁化合物BiFeO3、HoMnO3、TbMn2O5。将研究外延薄膜和单晶样品，以及使用激光烧蚀沉积和电子束光刻制成的纳米结构样品。这种研究方法是进步的，因为它在实验上将复杂材料中强相关电子的研究扩展到晶格长度尺度。如果成功，这项研究将使基于各种量子有序现象的新型电子设备的技术创新成为可能。这种“量子”设备在信号处理、信息存储以及量子计算方面具有重要的应用潜力。

The past few decades have seen a wealth of novel electron-ordering phenomena discovered in complex oxide and intermetallic materials. These phenomena range from unconventional superconductivity and colossal magnetoresistance to magnetoelectric multiferroism. Recent advances in nanofabrication and nanoprobetechniques, together with progress in cryomagnetic instrumentation, have enabled these materials to be studiedat very short length scales with controlled geometries and under extreme thermodynamic conditions.My proposed research is to apply a combination of nanofabrication, nanoprobe and cryomagnetic techniques on various complex oxides and novel intermetallics. The materials include: the high-Tc superconductors YBa2Cu3O6+x and Tl-doped cuprates; the heavy-fermion superconductors CeCoIn5, PrOs4Sb12, CePt3Si; the colossal magnetoresistive (CMR) compound La0.7Ca0.3MnO3; and the multiferroic compounds BiFeO3, HoMnO3, TbMn2O5.Both epitaxial thin-film and single crystal samples will be studied, as well as nanostructured samples made using laser ablated deposition and electron beam lithography.  This research approach is progressive in that it experimentally extends the study of strongly-correlated electrons in complex materials to crystal-lattice length scales.If successful, the proposed research could enable technological innovations in new forms of electronic devices based on various quantum-ordered phenomena. Such "quantum" devices would have significant applicationpotentials in signal processing, information storage, as well as quantum computing.