Quadric Conformal Metamaterials with Torus-Knotted Coils and Kerf-Structured Panels for Magnetic Resonance Imaging

Motivation: Maximizing signal-to-noise ratio (SNR) is crucial for MRI. Metamaterials significantly enhance SNR as innovative hardware, but their effectiveness is often limited when adapting to complex human body surfaces. Goal(s): To develop metamaterials that conform to human body surfaces. Approach: A prototype metamaterial with torus-knotted coils and kerf-structured panels was designed to conform to quadric surfaces, which are challenging to achieve with conventional structures. The SNR of MRI images was evaluated. Results: The metamaterial maintained 80% magnetic field enhancement under 20% deformation. The maximum SNR enhancement achieved was 9 times with an enhancement depth of 80 mm. Impact: The proposed metamaterial achieves 9-fold SNR enhancement and is suitable for applications in joint and head MRI. These findings suggest possibilities for wearable metamaterials adaptable to various human body surfaces by incorporating further stiffness control.