The innovation engine for new materials

Marie Niederlaender

Marie Niederlaender


Saarland University




Brian Haidet

Faculty Sponsor(s): 

Kunal Mukherjee

Faculty Sponsor's Department: 


Project Title: 

Surface Functionalization and Capping of Diamond NV Centers by Molecular Beam Epitaxy

Project Description: 

In recent years nitrogen vacancy (NV) centers in diamond have drawn much attention as a two-state quantum system, which is of high interest for quantum technology. These defects in the crystal lattice of diamond have potential to act as solid state qubits which have comparably long coherence times and can be read out and controlled optically. A major drawback however, is frequent unwanted interaction between the NV centers and surface spins, which results in loss of coherence. In collaboration with the Jayich group our novel approach to this outstanding problem utilizes the interaction between near-surface NV centers and single atoms, controllably placed on and bound to the diamond surface (adatoms). As a first step we deposited indium adatoms on diamond substrates containing shallow NVs, using molecular-beam epitaxy (MBE). Utilizing ion scattering spectroscopy (ISS) and X-ray photoelectron spectroscopy (XPS), the atomic coverage and composition of partial monolayers of indium are quantified with calibration samples of 100% and 0% indium coverage. The MBE growth rate is calibrated using a thick layer of deposited indium. Additional capping of the surface with inert atoms serves to minimize the decohering effects due to surface contaminants. The interactions of the adatoms with the NVs, as inferred through changes in coherence times, will be measured using confocal and wide field microscopy. Developing and measuring ultra-sparse adatom layers enables the fabrication of structures where individual NV centers can be observed interacting with individual adatoms. With this method, we hope to build interacting hybrid quantum systems with long coherence times, an important component for next generation quantum devices.