Sensitive superconducting quantum magnetometer

Watt W. Webb

Magnetometers of remarkable sensitivity utilizing superconducting quantum flux detectors have recently become available. The mechanisms of operation and the present capabilities of these magnetometers and related instruments are described from an elementary viewpoint.

Вадим Васильевич Данилов, K. K. Likharev

Hiraku Toida, Koji Sakai, Tetsuhiko Teshima +3 more

In the race to develop superconducting quantum computers, superconducting quantum circuit technology has made remarkable progress.The technology has also been applied to quantum sensing, especially highly sensitive magnetometers.The target of on-chip measurement by superconducting quantum sensors has thus far been limited to impurities in semiconductors.However, the range of applications is not limited to such hard materials.This article describes the detection of ferric ions in neurons with a high-sensitivity, high-spatial-resolution magnetometer using a superconducting flux qubit.

Vladimir Polushkin

Rujie Li, Wei Quan, Wenfeng Fan +4 more

Atomic magnetometer (AM) operated in a spin-exchange relaxation-free (SERF) regime features superior sensitivity and non-cryogenic operation, and thus is competitive with the best superconducting quantum interference devices. Previously, SERF AM with fT/Hz 1/2 level sensitivity commonly acted as a single-axis sensor. Here we demonstrate a dual-axis SERF AM capable of simultaneously and independently detecting x - and y -field components with a sensitivity of 20 fT/Hz 1/2 . As there is no necessity to worry about the cross-talk effects arising from field modulations, the dual-axis scheme proposed here is of particular interest to AM array and hence the biomagnetic applications.

K. K. Likharev, Oleg V. Snigirev, S.S. Tinchev