Magnetic field sensing using a driven double quantum dot

• Published in: Physica. E, Low-dimensional systems & nanostructures Vol. 42; no. 4; pp. 895 - 898
• Main Authors: Giavaras, G., Wabnig, J., Lovett, B.W., Jefferson, J.H., Briggs, G.A.D.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 01-02-2010; Elsevier
• Subjects: Condensed matter: electronic structure, electrical, magnetic, and optical properties; Detector; Driven double dot; Electronic structure and electrical properties of surfaces, interfaces, thin films and low-dimensional structures; Electronic transport in multilayers, nanoscale materials and structures; Exact sciences and technology; Physics; Quantum dots; Spin resonance; Spin resonance; Detector; Driven double dot; Magnetic field measurement; Spin relaxation; Microwave radiation; Quantum dots; Field gradients; Hubbard model; Transport processes; Level anticrossing
• ISSN: 1386-9477; 1873-1759
• DOI: 10.1016/j.physe.2009.11.138

A microwave-driven double dot system is investigated as a detector for probing a magnetic field gradient. The two dots are connected to metallic leads and a source–drain current flows under microwave irradiation. The induced current as a function of the external magnetic field exhibits resonance effects that depend directly on the local field gradient and any difference in the
g-factors between the dots. The properties of the dot detector with respect to temperature, interdot hopping and the magnitude of the field gradient are examined. We demonstrate that the main factor limiting sensitivity is spin relaxation and discuss the issues in applying the method to single spin detection.