Ferrimagnets, which contain the advantages of both ferromagnets(detectable moments) and antiferromagnets(ultrafast spin dynamics), have recently attracted great attention. Here, we report the optimization of epitaxial...Ferrimagnets, which contain the advantages of both ferromagnets(detectable moments) and antiferromagnets(ultrafast spin dynamics), have recently attracted great attention. Here, we report the optimization of epitaxial growth of a tetragonal perpendicularly magnetized ferrimagnet Mn_(2)Ga on MgO. Electrical transport, magnetic properties and the anomalous Hall effect(AHE) were systematically studied. Furthermore, we successfully integrated high-quality epitaxial ferrimagnetic Mn_(2)Ga thin films onto ferroelectric 0.7PbMg_(1/3)Nb_(2/3)O_(3)–0.3PbTiO_(3) single crystals with a MgO buffer layer. It was found that the AHE of such a ferrimagnet can be effectively modulated by a small electric field over a large temperature range in a nonvolatile manner. This work thus demonstrates the great potential of ferrimagnets for developing high-density and low-power spintronic devices.展开更多
The emerging Ni-based superconducting oxide thin films are rather intriguing to the entire condensed matter physics. Here, we report some brief experimental results on transport measurements for a 14-nm-thick supercon...The emerging Ni-based superconducting oxide thin films are rather intriguing to the entire condensed matter physics. Here, we report some brief experimental results on transport measurements for a 14-nm-thick superconducting Nd_(0.8)Sr_(0.2)NiO_(2)/SrTiO_(3) thin-film heterostructure with an onset transition temperature of~9.5 K. Photoluminescence measurements reveal that there is negligible oxygen vacancy creation in the SrTiO_(3) substrate during thin-film deposition and post chemical reduction for the Nd_(0.8)Sr_(0.2)NiO_(2)/SrTiO_(3) heterostructure. It was found that the critical current density of the Nd_(0.8)Sr_(0.2)NiO_(2)/SrTiO_(3) thin-film heterostructure is relatively small, ~4×10^(3) A·cm^(-2). Although the surface steps of SrTiO_(3) substrates lead to an anisotropy for in-plane resistivity, the superconducting transition temperatures are almost the same. The out-of-plane magnetotransport measurements yield an upper critical field of~11.4 T and an estimated in-plane Ginzburg–Landau coherence length of~5.4 nm. High-field magnetotransport measurements up to 50 T reveal anisotropic critical fields at 1.8 K for three different measurement geometries and a complicated Hall effect. An electric field applied via the SrTiO_(3) substrate slightly varies the superconducting transition temperature. These experimental results could be useful for this rapidly developing field.展开更多
基金the National Natural Science Foundation of China(Nos.52121001,51822101,51861135104 and 51771009)。
文摘Ferrimagnets, which contain the advantages of both ferromagnets(detectable moments) and antiferromagnets(ultrafast spin dynamics), have recently attracted great attention. Here, we report the optimization of epitaxial growth of a tetragonal perpendicularly magnetized ferrimagnet Mn_(2)Ga on MgO. Electrical transport, magnetic properties and the anomalous Hall effect(AHE) were systematically studied. Furthermore, we successfully integrated high-quality epitaxial ferrimagnetic Mn_(2)Ga thin films onto ferroelectric 0.7PbMg_(1/3)Nb_(2/3)O_(3)–0.3PbTiO_(3) single crystals with a MgO buffer layer. It was found that the AHE of such a ferrimagnet can be effectively modulated by a small electric field over a large temperature range in a nonvolatile manner. This work thus demonstrates the great potential of ferrimagnets for developing high-density and low-power spintronic devices.
基金financially supported by the National Natural Science Foundation of China(Nos.51822101,51861135104 and 51771009)。
文摘The emerging Ni-based superconducting oxide thin films are rather intriguing to the entire condensed matter physics. Here, we report some brief experimental results on transport measurements for a 14-nm-thick superconducting Nd_(0.8)Sr_(0.2)NiO_(2)/SrTiO_(3) thin-film heterostructure with an onset transition temperature of~9.5 K. Photoluminescence measurements reveal that there is negligible oxygen vacancy creation in the SrTiO_(3) substrate during thin-film deposition and post chemical reduction for the Nd_(0.8)Sr_(0.2)NiO_(2)/SrTiO_(3) heterostructure. It was found that the critical current density of the Nd_(0.8)Sr_(0.2)NiO_(2)/SrTiO_(3) thin-film heterostructure is relatively small, ~4×10^(3) A·cm^(-2). Although the surface steps of SrTiO_(3) substrates lead to an anisotropy for in-plane resistivity, the superconducting transition temperatures are almost the same. The out-of-plane magnetotransport measurements yield an upper critical field of~11.4 T and an estimated in-plane Ginzburg–Landau coherence length of~5.4 nm. High-field magnetotransport measurements up to 50 T reveal anisotropic critical fields at 1.8 K for three different measurement geometries and a complicated Hall effect. An electric field applied via the SrTiO_(3) substrate slightly varies the superconducting transition temperature. These experimental results could be useful for this rapidly developing field.
