Project R-13269

Electrically Read Diamond Spin Qubits Entanglement (Research)

Nitrogen-vacancy (NV) centers in diamond can offer a scalable, room temperature alternative to cryogenic superconducting qubits in the development of quantum applications. The novel PDMR readout technique, based on the creation of electron-hole pairs by the NV centers, allows to reduce the measurement system size. The charge carriers are transported through the diamond material and an analog photocurrent signal is detected. This proposed project aims to reach the standard quantum limit (SQL), using electron counting devices based on HEMT or single electron transistors, which can boost the sensitivity of advanced quantum devices. When electrons/holes can travel freely (ballistic transport) to the collecting electrode, it can be verified if the NV center is a single electron source using the second order correlation function. The use of SQL PDMR will be investigated in nanoscale quantum devices and be used in dipole-dipole qubit entanglement. To achieve this, the purity of the diamond material needs to be optimized using defect spectroscopy on the single defect level and NV fabrication should be as deterministic as possible. Quantum controls need to be fabricated on the diamond surface for operation at low temperatures (∼100 nm pitch) and room temperature (∼20 nm pitch), optimized for low cross-talk and MW-induced noise. By scanning the temperature from 1,5 K to room temperature, the temperature limit for SQL and ballistic operation of the single NV center will be determined.

01 November 2022 - 31 October 2026