Charge carrier injection performed in Pr0.7Ca0.3MnO3 (PCMO) hetero-structure junctions exhibits stable without electric fields and dramatic changes in both resistances and interface barriers, which are entirely different from behaviors of semiconductor devices. Disappearance and reversion of interface barriers suggest that the adjustable resistance switching of such hetero-structure oxide devices should associate with motion of charge carriers across interfaces. The results suggested that injected carriers should be still staying in devices and resulted in changes in properties, which guided to a carrier self-trapping and releasing picture in strongly correlated electronic framework. Observations in PCMO and oxygen deficient CeO2 devices show that oxides as functional materials could be used in microelectronics with some novel properties, in which interface is very important.
Temperature dependance of the tunneling density of states in sub-micron planar metal / oxide / graphene junctions
我们提出了亚微米金属/绝缘体/石墨烯平面隧道结的隧穿测量到室温。我们观察到了一个与栅极无关的能隙，这是以前只能通过低温STM观察到的。Zhang等人，4，627（2008）]。在150 K以上没有能隙出现，这比从公认的平均场模型[T. O. Wehling等人，Phys. Rev. Lett. 101，216803（2008）]。我们表明，考虑到一个额外的振动效应的面外声子软模式的间隙可能会消失，从测量温度远低于计算的$T_{c}$。
Oxide heterostructures are a new class of materials by design, that open the possibility for engineering challenging electronic properties, in particular correlation effects beyond an effective single-particle description. This short review tries to highlight some of the demanding aspects and questions, motivated by the goal to describe the encountered physics from first principles. The state-of-the-art methodology to approach realistic many-body effects in strongly correlated oxides, the combination of density functional theory with dynamical mean-field theory, will be briefly introduced. Dis…
We report a complementary metal oxide semiconductor (CMOS) technology compatible ferroelectric tunnel junction memristor grown directly on top of a Silicon substrate using a scandium doped aluminum nitride as the ferroelectric layer.
In the quest to understand high-temperature superconductivity in copper oxides, a vigorous debate has been focused on the pseudogap - a partial gap that opens over portions of the Fermi surface in the 'normal' state above the bulk critical temperature ($T_{c}$). The pseudogap has been attributed to precursor superconductivity, to the existence of preformed pairs, or to competing orders such as charge-density waves. A direct determination of the charge of carriers as a function of temperature and bias could help resolve among these alternatives. Here, we report measurements of the shot noise of…
The exchange bias effect is an essential component of magnetic memory and spintronic devices. Whereas recent research has shown that anisotropies perpendicular to the device plane provide superior stability against thermal noise, it has proven remarkably difficult to realize perpendicular exchange bias in thin-film structures. Here we demonstrate a strong perpendicular exchange bias effect in heterostructures of the quasi-two-dimensional canted antiferromagnet La$_2$CuO$_4$ and ferromagnetic (La,Sr)MnO$_3$ synthesized by ozone-assisted molecular beam epitaxy. The magnitude of this effect can b…
Using micromagnetic simulations, we have modelled the formation of imprinted merons and anti-merons in cobalt overlayers of different thickness (1-8 nm), stabilised by interfacial exchange with antiferromagnetic vortices in $α$-Fe2O3. Structures similar to those observed experimentally could be obtained with reasonable exchange parameters, also in the presence of surface roughness. We produce simulated meron|antimeron images by magnetic force microscopy (MFM) and nitrogen-vacancy (N-V) centre microscopy, and established signatures of these topological structures in different experimental confi…
Oxide heterointerfaces constitute a rich platform for realizing novel functionalities in condensed matter. A key aspect is the strong link between structural and electronic properties, which can be modified by interfacing materials with distinct lattice symmetries. Here we determine the effect of the cubic-tetragonal distortion of $\text{SrTiO}_3$ on the electronic properties of thin films of $\text{SrIrO}_3$, a topological crystalline metal hosting a delicate interplay between spin-orbit coupling and electronic correlations. We demonstrate that below the transition temperature at 105 K, $\tex…
Using interlayer interaction to control functional heterostructures with atomic-scale designs has become one of the most effective interface-engineering strategies nowadays. Here, we demonstrate the effect of a crystalline LaFeO3 buffer layer on amorphous and crystalline LaAlO3/SrTiO3 heterostructures. The LaFeO3 buffer layer acts as an energetically favored electron acceptor in both LaAlO3/SrTiO3 systems, resulting in modulation of interfacial carrier density and hence metal-to-insulator transition. For amorphous and crystalline LaAlO3/SrTiO3 heterostructures, the metal-to-insulator transitio…
