Tungsten Ditelluride: Synthesis, Structure, and Magnetoresistance Property

Abstract

Tungsten ditelluride (WTe2) is arising as an attractive material in magnetoresistance (MR) properties filed. The magnetoresistance properties of WTe2 makes it an ideal material for its magnetoresistive heads of computer and magnetic sensor device applications. So far, people have developed various controlled synthesis methods to produce large‐quantity uniform flat WTe2 crystals. Nevertheless, none of the methods are sustainable, some methods use reducing gases, and some use very long heat preservation, and the process is very complicated. Here, a mild and fast self‐flux method is described for WTe2 synthesis that can avoid producing reducing gases. After conducting structural and physical tests, it is found that annealing time is critical for WTe2 structure formation. Long annealing time improves the crystallinity of WTe2 and makes its texture more obvious, increasing the conductivity of WTe2. Therefore, it will lead to the anomalous nonsaturating positive magnetoresistance with different field dependent behaviors, reaching the ultrastrong magnetoresistive value of 1040% at 5 K and 14 T. The results provide a sustainable approach for uniform WTe2 crystal synthesis, which will benefit the large‐quantity production of WTe2 magnetoresistive materials.

Femtosecond Laser Thinning for Resistivity Control of Tungsten Ditelluride Thin-Films Synthesized from Sol-Gel Deposited Tungsten Oxide

“…It is obtained that the highest intensity peaks have a binding energy (BE) of 2.7 eV above the BE of W 3d core level for the pure metal [54]. Several studies show that a BE displacement of less than 1 eV is expected for the W 3d core level of the W-Te bond [55,56]. Therefore, by comparison it can be deduced that the peaks obtained at BE of 1783 and 1845 eV (Fig.…”

“…5) correspond to the 3d 5/2 y 3d 3/2 core levels of WTe 2 , respectively. The smaller peaks at 1823 and 1885 eV are due to a non-stoichiometric oxide since they are at a higher BE [55,56]. In Fig.…”

Direct Growth of Low Thermal Conductivity WTe2 Nanocrystalline Films on W Films

“…The availability of lower thermal conductivity WTe 2 films gives rise to more potential for its use in electronic devices. However, the inactivity of tellurium makes it more challenging to prepare WTe 2 films, making industrial preparation crucial for their next production applications [ 11 , 12 , 13 , 14 , 15 , 16 ]. Although there have been some studies on WTe 2 , there have been relatively few technical studies on the direct growth of WTe 2 on W thin films.…”

Observation of an anisotropic ultrafast spin relaxation process in large-area WTe2 films

“…Topological Weyl semimetals have gained the growing interest owing to their remarkably exotic physics for potential applications. [1][2][3][4] Specifically, a representative Weyl topological semimetal, [5][6][7] WTe2, has a unique band structure, enabling a rich spectrum of alluring properties, including extremely large nonsaturating magnetoresistance, 8 pressure-/gate-tunable superconductivity, 9,10 quantum spin Hall effect, 11 nonlinear Hall effect, [12][13][14] large nonlinear optical properties [15][16][17] and notable spin-charge conversion properties. [18][19][20] Integration into the next-generation electronic/spintronic devices, [21][22][23][24] the ultrafast dynamics of low-dimension materials, e.g.…”