Phys.org  October 2, 2024 Optically addressable spin defects in 3D crystals and 2D van der Waals (vdW) materials are important for nanoscale quantum sensing. However, optically detected magnetic resonance of localized spin defects in a nanotube has not been observed. A team of researchers in the US (Purdue University, Indiana University) found single spin color centers in boron nitride nanotubes (BNNTs) at room temperature which suggested that BNNT spin defects possess a spin S = 1/2 ground state without an intrinsic quantization axis, leading to orientation-independent magnetic field sensing. Using this unique feature, they observed anisotropic magnetization of a 2D […]