Spin imaging of two-dimensional crystals and van der Waals heterostructures via nitrogen-vacancy magnetometry with light

Two-dimensional (2D) magnets and superconductors have opened the door to explore new physical scenarios that were not available until just very recently.

Moreover, new emergent properties can appear when different 2D crystals are assembled forming van der Waals heterostructures (vdWHs).

For example, some scientific open-questions in this field are i) the sensing and control of 2D magnons, ii) the appearance of fractionalized excitacions in 2D quantum spin liquids (QSL) or iii) the emergence of topological superconductivity in ferromagnet/superconductor vdWHs.In all the previous cases, the spin is the key element, being necessary to detect it with high spatial resolution and sensitivity.

This is a current challenge for most of the common experimental characterization techniques as heat capacity, inelastic neutron scattering or muon spectroscopy, just to cite some, due to the few number of atoms in a 2D crystal.

As a promising experimental tool, nitrogen-vacancy (NV) centers in diamond have shown to be ideal magnetic probes at the nanoscale.In this project, we propose to explore strongly correlated phenomena in the 2D limit by imaging the spin in 2D magnets (as in CrSBr) or 2D frustrated magnets (in the QSL 1T-TaS2) as well as van der Waals heterostructures (as superconducting NbSe2 in proximity to the metamagnet CrSBr) by using NV magnetometry.

It combines in a win-to-win scenario my expertise for dealing with 2D crystals and vdWHs under inert atmosphere conditions together with the knowledge and currently available equipment at TU Delft offered by prof. van der Sar and prof. van der Zant on NV magnetometry and correlated materials.The successful completion of the proposed experiments will generate ground breaking results in highly correlated systems (QSLs, 2D superconductors, 2D magnets and vdWHs) that will advance the field and bring new cutting edge field directions of potential interest for spintronics and quantum technologies.