Highly Sensitive Tunable Magnetometer Based on Superconducting Quantum Interference Device

Abstract

In the present article, experimental results regarding fully integrated superconducting quantum interference devices (SQUID), including a circuit to tune and optimize the main sensor device characteristics, are reported. We show the possibility of modifying the critical current of a SQUID magnetometer in liquid helium by means of a suitable heating circuit. This allows us to improve the characteristics of the SQUID sensor and in particular to optimize the voltage–magnetic flux characteristic and the relative transfer factor (responsivity) and consequently to also improve the flux and magnetic field noise. It is also possible to reset the SQUID sensor in case of entrapment of magnetic flux, avoiding taking it out of the helium bath. These results are very useful in view of most SQUID applications such as those requiring large multichannel systems in which it is desirable to optimize and eventually reset the magnetic sensors in a simple and effective way.

The Effect of Sleep Deprivation on Brain Fingerprint Stability: A Magnetoencephalography Validation Study

“…The helmet included 154 SQUID magnetometers as measurement channels, while another 9 SQUIDs were organized into three triplets and positioned further away from the measurement surface to measure the environmental noise. Such sensors consist of fully integrated SQUID magnetometers based on a Ketchentype design and include a superconducting flux transformer inductively coupled to the SQUID loop in a washer shape [28]. Since the readout electronics require a negative feedback circuit to linearize the output extending the linear dynamic range, the magnetometer also included a feedback coil in a bipolar shape to minimize the crosstalk between the neighboring channels.…”

“…Since the readout electronics require a negative feedback circuit to linearize the output extending the linear dynamic range, the magnetometer also included a feedback coil in a bipolar shape to minimize the crosstalk between the neighboring channels. All coils and a resistor network for the SQUID Such sensors consist of fully integrated SQUID magnetometers based on a Ketchentype design and include a superconducting flux transformer inductively coupled to the SQUID loop in a washer shape [28]. Since the readout electronics require a negative feedback circuit to linearize the output extending the linear dynamic range, the magnetometer also included a feedback coil in a bipolar shape to minimize the crosstalk between the neighboring channels.…”

Wide Linearity Range 3D Magnetic Sensor and Angular Position Detector Based on a Single FePt Spin–Orbit Torque Device

“…A variety of magnetic sensors have been widely employed in geomagnetic navigation, biomagnetic sensing, and the automotive industry. , Especially, the demand for magnetoresistive sensors, including anisotropic magnetoresistance (AMR), giant magnetoresistance (GMR), and tunnel magnetoresistance (TMR) sensors, is increasing dramatically due to their low cost, robust endurance, and high reliability in the automotive industry. − Besides, the superconducting quantum interference device (SQUID) is the most sensitive technology for some ultrasensitive electronic and magnetic measurements . However, most of the commonly used magnetic sensors create an output electrical signal that is proportional to the scalar quantity of the magnetic field along a principal axis.…”

“…9−11 Besides, the superconducting quantum interference device (SQUID) is the most sensitive technology for some ultrasensitive electronic and magnetic measurements. 12 However, most of the commonly used magnetic sensors create an output electrical signal that is proportional to the scalar quantity of the magnetic field along a principal axis. To detect the field components in three orthogonal directions directly, the traditional approach is to integrate multiple sensitive devices with their sensitive directions along the three coordinate axes.…”

A Review of the Current State of Magnetic Force Microscopy to Unravel the Magnetic Properties of Nanomaterials Applied in Biological Systems and Future Directions for Quantum Technologies

“…SQUID consists of placing a sample in a magnetic field and measuring the magnetic moment of the sample as a function of the applied field strength [ 9 ]. Moreover, controlling the applied current by the integration of a heating resistor on the same sample chip makes tunable the SQUID sensor device [ 10 ]. This technology has been applied to measure the magnetic properties of biological systems such as magnetosomes from magnetotactic bacteria [ 11 ], mesenchymal stem cells for tissue engineering applications [ 12 ], or the characterization of iron oxide nanoparticles in biological samples [ 13 ], and for the magnetic separation of microplastic bodies from water resources [ 14 ], respectively.…”