Evolution of electrical and magnetotransport properties with lattice strain in La_0.7Sr_0.3MnO₃ film*

Abstract

In this paper, we investigate the effects of lattice strain on the electrical and magnetotransport properties of La0.7Sr0.3MnO3 (LSMO) films by changing film thickness and substrate. For electrical properties, a resistivity upturn emerges in LSMO films, i.e., LSMO/STO and LSMO/LSAT with small lattice strain at a low temperature, which originates from the weak localization effect. Increasing film thickness weakens the weak localization effect, resulting in the disappearance of resistivity upturn. While in LSMO films with a large lattice strain (i.e., LSMO/LAO), an unexpected semiconductor behavior is observed due to the linear defects. For magnetotransport properties, an anomalous in-plane magnetoresistance peak (pMR) occurs at low temperatures in LSMO films with small lattice strain, which is caused by two-dimensional electron gas (2DEG). Increasing film thickness suppresses the 2DEG, which weakens the pMR. Besides, it is found that the film orientation has no influence on the formation of 2DEG. While in LSMO/LAO films, the 2DEG cannot form due to the existence of linear defects. This work can provide an efficient way to regulate the film transport properties.

Low-temperature ferromagnetism in tensile-strained LaCoO2.5 thin film

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Gate-controlled magnetic transitions in Fe3GeTe2 with lithium ion conducting glass substrate*

“…FGT with such intrinsic ferromagnetic property and its metallic nature in the 2D limit gives us with a good material platform: we could study its magnetic properties through electrical transport measurement, and the interplay of spin and charge degrees of freedom provides more possibilities in device concepts based on magnetic vdW heterostructures. [15][16][17] The magnetic properties of magnetic materials can be modulated with different methods, such as strain [18][19][20][21] and electrical-gating. [12,22] Gate-controlled magnetism is an attractive way to realize magnetoelectronic devices.…”

Phase transition-induced superstructures of β-Sn films with atomic-scale thickness*

“…Since the discovery and characterization of graphene, [1,2] the novel two-dimensional (2D) materials, especially for monoelemental 2D materials, have been the subject of an increasing area of research due to their exotic non-trivial topological properties and potential applications. [3][4][5][6][7][8][9][10] In the periodic table, most of 2D monoelemental materials, consisting of the elements in the main group of IIIA, IVA, and VA, have been successfully prepared, such as borophene, [11][12][13][14] silicene, [15][16][17] antimonene, [18][19][20][21] bismuthine, [5,22,23] and so on. [24][25][26] Among them, the 2D materials consisted of heavy elements have been predicted as topological insulators with enhanced bulk gap and nontrivial edge state due to their strong spin-orbit coupling (SOC).…”