Overview
This research presents a magnetic resonance imaging (MRI) method for $\mu$L-scale samples, employing an optically pumped magnetometer (OPM) under low magnetic field conditions. The approach facilitates one- and two-dimensional imaging capabilities.
Research Context
The study addresses the need for practical and sensitive low-field MRI. It specifically focuses on imaging $\mu$L-scale samples, an application domain where conventional MRI techniques may face limitations related to field strength and sensitivity. The use of an OPM is central to this low-field strategy, departing from traditional signal-pickup coils.
Approach
The methodology involved a simple experimental setup wherein a commercial OPM was positioned directly adjacent to the sample. This configuration eliminated the need for intermediary signal-pickup coils. The imaging was performed at a magnetic field strength of approximately 10 $\mu$T, which is near the Earth's magnetic field.
The system was designed to achieve:
- A field of view of 1 cm.
- Sub-millimeter Fourier-limited resolution.
- One- and two-dimensional imaging.
Findings
The demonstrated approach achieved practical and sensitive low-field magnetic resonance imaging of $\mu$L-scale samples. Key findings include:
- Successful performance of one-dimensional imaging.
- Successful performance of two-dimensional imaging.
- Imaging conducted with a 1 cm field of view.
- Attainment of sub-millimeter Fourier-limited resolution.
- Operation at a magnetic field of 10 $\mu$T.
The effectiveness of this setup with an OPM directly adjacent to the sample was observed without the inclusion of signal-pickup coils.
Why This Matters
The established method enables two specific outcomes:
- High-throughput, low-field MRI of fluidic and tissue samples.
- A quantitative benchmark for the sensitive volume surrounding the OPM.