Sudipta Dubey1
IIT Kanpur1
Atomically thin, semiconducting, transition metal dichalcogenides, with their band gap being direct in monolayer have intriguing opto-electronic properties like valley selective circular dichroism, spin-valley locking, chiral phonons at high symmetry points of honeycomb lattice. Single photon emitters have been observed in these materials which are believed to be excitons trapped in defect potential. These quantum emitters inherit the two-dimensional nature and valley degree of freedom from the host material. I will talk about these localized excitons, where we observed entanglement between photons emitted from these quantum dots and chiral phonons in the host material <sup>[1]</sup>. For the charged localized excitons having an excess single spin, we observed that we can initialize a single spin optically <sup>[2]</sup>, taking the advantage of valley selective circular dichroism and spin-valley locking of the host material. I will conclude by discussing the advantage that the two-dimensional nature of these materials presents in easily forming a van der Waal heterostructure, where the localized excitons have a permanent dipole moment and their emissions can be tuned electrically <sup>[3]</sup>.<br/>[1] Chen, X., Lu, X., Dubey, S. <i>et al</i>., Nature Physics 15, 221 (2019)<br/>[2] Lu, X., Chen, X., Dubey, S. <i>et al</i>., Nature Nanotechnology 14, 426 (2019)<br/>[3] Li, W., Lu, X., Dubey, S., Devenica, L. and Srivastava, A., Nature Materials 19, 624 (2020)