Applied Physics Seminar

We have developed a deterministic ion implantation method to insert phosphorus atoms into silicon for quantum computer technology based on potentially scalable engineered single donor atom devices.  We engineer nano-scale silicon CMOS devices with implanted ³¹P atoms in which spin states of selected atoms can be programed and read-out by means of associated gate electrodes.  In natural silicon these devices have an electron coherence time exceeding 200 µs and nuclear spin coherence times for ionized donors of 60 ms. Over the past two years we have succeeded in implanting ³¹P donor atoms into isotopically enriched ²⁸Si and we find the ³¹P nuclear spin coherence time to be greater than 30 seconds showing exceptional promise and the robustness of the quantum system to imperfections in the nearby gate oxide and electrode metals.  This presentation describes our approach to take this technology to the next stage by building deterministic arrays of single atoms with the goal of 6 nm positioning precision as a pathway to a large scale device based on the most important material for information technology: silicon.