EAGER: Quantum Manufacturing: Supporting Future Quantum Applications by Developing a Robust, Scalable Process to Create Diamond Nitrogen-Vacancy Center Qubits

Duke University, Durham NC

Investigators

Abstract

This EArly-concept Grant for Exploratory Research (EAGER) Quantum Manufacturing award will support innovative research to demonstrate a new approach and reveal new knowledge on the creation of nitrogen-vacancy (NV) color centers in diamond for quantum bit implementation. Quantum information applications, such as quantum computing, communications, and sensing, rely on the implementation of reproducible and robust quantum bits, or qubits. Numerous materials and systems have been identified to create qubits, but diamond is of particular interest because its NV centers are very stable and provide relatively long room temperature coherence times. However, the creation of color centers in wide -bandgap semiconductors, such as diamond, is challenging. Qubit fabrication in these materials has been primarily based on conventional microelectronics manufacturing techniques. While these approaches have provided a basis for diamond-based qubit system studies, conventional microelectronic processing techniques are not optimal for color center manufacturing. To change this, the research will utilize a robust and scalable diamond growth technique coupled with carbon nanotube electron beam irradiation to create the defects. While NV centers in diamond have been shown to be efficacious for qubit realization, current manufacturing processes remain challenging. Most implementations rely on the post- processing identification of effective qubits created using ion implantation and annealing. Specific manufacturing challenges relate to the difficulties in balancing defect center creation and diamond defect and strain introduction, control of the spatial location of NV centers, and the difficulty in scaling processes to large-area diamond wafers. The new process rests on the synthesis of large-area diamond prototype wafers and the use of arrays of carbon-nanotube bundles enabling the controlled introduction of NV centers using field emission and electron bombardment. This new approach enables more control of the energy required to create NV centers allowing the trade-off of qubit creation and defect production, as well as significant advances in the control of spatial positioning of qubits. The results from this research will benefit the US economy and society. Quantum information systems will significantly enhance technologies for security, communications, biomedical sensing, and computing. This research involves several disciplines including manufacturing, materials science, and electrical engineering. The multi-disciplinary approach will help broaden the participation of underrepresented groups in research and will positively impact engineering education. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.