By using first-principles calculations, we propose that ZrSiO can be looked
as a three-dimensional (3D) oxide weak topological insulator (TI) and its
single layer is a long-sought-after 2D oxide TI with a band gap up to 30 meV.
Calculated phonon spectrum of the single layer ZrSiO indicates it is
dynamically stable and the experimental achievements in growing oxides with
atomic precision ensure that it can be readily synthesized. This will lead to
novel devices based on TIs, the so called "topotronic" devices, operating under
room-temperature and stable when exposed in the air. Thus, a new field of
"topotronics" will arise. Another intriguing thing is this oxide 2D TI has the
similar crystal structure as the well-known iron-pnictide superconductor
LiFeAs. This brings great promise in realizing the combination of
superconductor and TI, paving the way to various extraordinary quantum
phenomena, such as topological superconductor and Majorana modes. We further
find that there are many other isostructural compounds hosting the similar
electronic structure and forming a WHM-family with W being Zr, Hf or La,
H being group IV or group V element, and M being group VI one.Comment: adding results of phonon spectrum, supported substrate and binding
energy. Related with our recent preprints for 2D TIs: arXiv:1507.01172,
arXiv:1503.09040 and arXiv:1508.0522
