Driving a spin‐logic circuit requires the production of a large output signal by spin‐charge interconversion in spin‐orbit readout devices. This should be possible by using topological insulators, which are known for their high spin‐charge interconversion efficiency. However, high‐quality topological insulators have so far only been obtained on a small scale, or with large scale deposition techniques that are not compatible with conventional industrial deposition processes. The nanopatterning and electrical spin injection into these materials have also proven difficult due to their fragile structure and low spin conductance. The fabrication of a spin‐orbit readout device from the topological insulator Sb2Te3 deposited by large‐scale industrial magnetron sputtering on SiO2 is presented. Despite a modification of the Sb2Te3 layer structural properties during the device nanofabrication, a sizeable output voltage is measured that can be unambiguously ascribed to a spin‐charge interconversion process. The results pave the way for the integration of layered van der Waals materials in spin‐logic devices.

Spin-orbit effects appearing in topological insulators (TI) and at Rashba interfaces are currently revolutionizing how we can manipulate spins and have led to several newly discovered effects, from spin-charge interconversion and spin-orbit torques to novel magnetoresistance phenomena. In particular, a puzzling magnetoresistance has been evidenced, bilinear in electric and magnetic fields. Here, we report the observation of bilinear magnetoresistance (BMR) in strained HgTe, a prototypical TI. We show that both the amplitude and sign of this BMR can be tuned by controling, with an electric gate, the relative proportions of the opposite contributions of opposite surfaces. At magnetic fields of 1 T, the magnetoresistance is of the order of 1 % and has a larger figure of merit than previously measured TIs. We propose a theoretical model giving a quantitative account of our experimental data. This phenomenon, unique to TI, offer novel opportunities to tune the electrical response of surface states for spintronics.

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