Depth estimation is an important task in computer vision.Collecting data at scale for monocular depth estimation is challenging,as this task requires simultaneously capturing RGB images and depth information.Therefore,data augmentation is crucial for this task.Existing data augmentationmethods often employ pixel-wise transformations,whichmay inadvertently disrupt edge features.In this paper,we propose a data augmentationmethod formonocular depth estimation,which we refer to as the Perpendicular-Cutdepth method.This method involves cutting realworld depth maps along perpendicular directions and pasting them onto input images,thereby diversifying the data without compromising edge features.To validate the effectiveness of the algorithm,we compared it with existing convolutional neural network(CNN)against the current mainstream data augmentation algorithms.Additionally,to verify the algorithm’s applicability to Transformer networks,we designed an encoder-decoder network structure based on Transformer to assess the generalization of our proposed algorithm.Experimental results demonstrate that,in the field of monocular depth estimation,our proposed method,Perpendicular-Cutdepth,outperforms traditional data augmentationmethods.On the indoor dataset NYU,our method increases accuracy from0.900 to 0.907 and reduces the error rate from0.357 to 0.351.On the outdoor dataset KITTI,our method improves accuracy from 0.9638 to 0.9642 and decreases the error rate from 0.060 to 0.0598.
Flexible electronics/spintronics attracts researchers’attention for their application potential abroad in wearable devices,healthcare,and other areas.Those devices’performance(speed,energy consumption)is highly dependent on manipulating information bits(spin-orientation in flexible spintronics).In this work,we established an organic photovoltaic(OPV)/ZnO/Pt/Co/Pt heterostructure on flexible PET substrates with perpendicular magnetic anisotropy(PMA).Under sunlight illumination,the photoelectrons generated from the OPV layer transfer into the PMA heterostructure,then they reduce the PMA strength by enhancing the interfacial Rashba field accordingly.The coercive field(Hc)reduces from 800 Oe to 500 Oe at its maximum,and the magnetization can be switched up and down reversibly.The stability of sunlight control of magnetization reversal under various bending conditions is also tested for flexible spintronic applications.Lastly,the voltage output of sunlight-driven PMA is achieved in our prototype device,exhibiting an excellent angular dependence and opening a door towards solar-driven flexible spintronics with much lower energy consumption.
Rare-earth-free Mn-based binary alloy L1_(0)-MnAl with bulk perpendicular magnetic anisotropy(PMA) holds promise for high-performance magnetic random access memory(MRAM) devices driven by spin-orbit torque(SOT). However, the lattice-mismatch issue makes it challenging to place conventional spin current sources, such as heavy metals, between L1_(0)-MnAl layers and substrates. In this work, we propose a solution by using the B2-CoGa alloy as the spin current source. The lattice-matching enables high-quality epitaxial growth of 2-nm-thick L1_(0)-MnAl on B2-CoGa, and the L1_(0)-MnAl exhibits a large PMA constant of 1.04 × 10^(6)J/m^(3). Subsequently, the considerable spin Hall effect in B2-CoGa enables the achievement of SOT-induced deterministic magnetization switching. Moreover, we quantitatively determine the SOT efficiency in the bilayer. Furthermore, we design an L1_(0)-MnAl/B2-CoGa/Co_(2)MnGa structure to achieve field-free magnetic switching. Our results provide valuable insights for achieving high-performance SOT-MRAM devices based on L1_(0)-MnAl alloy.
Using micromagnetic simulations, we demonstrate the tilted perpendicular anisotropy-induced spin-orbit ratchet effect. In spin-orbit torque(SOT)-induced magnetization switching, the critical currents required to switch between the two magnetization states(upward and downward magnetization) are asymmetric. In addition, in the nanowire structure, tilted anisotropy induces formation of tilted domain walls(DWs). The tilted DWs exhibit a ratchet behavior during motion. The ratchet effect during switching and DW motions can be tuned by changing the current direction with respect to the tilting direction of anisotropy. The ratchet motion of the DWs can be used to mimic the leaky-integrate-fire function of a biological neuron, especially the asymmetric property of the “potential” and “reset” processes. Our results provide a full understanding of the influence of tilted perpendicular anisotropy on SOT-induced magnetization switching and DW motion, and are beneficial for designs of further SOT-based devices.
