Development of a Multichannel Atomic Magnetometer for Parallel Magnetic Resonance Imaging*

Magnetic resonance imaging (MRI) in the ultra-low field (ULF) regime is a promising method for anatomical imaging with multiple advantages over conventional several-Tesla MRI. The leading high-sensitivity multichannel ULF MRI was realized only with multichannel superconducting quantum interference devices (SQUIDs); however, the need for cryogenic infrastructure is a serious drawback. We aim to develop an alternative, more practical ULF MRI based on a high-sensitivity multichannel atomic magnetometers (AMs) and multiple flux transformers (FTs). AMs are currently the most sensitive non-cryogenic magnetic-field sensors. Our approach represents the first ULF MRI implementation using the novel technique, which has many innovative features such as acceleration of MRI, a large array of sensors based on a single large atomic vapor cell, reducing the cost of sensors ~10 times, and flexible design based on FTs. In this talk, we will describe the basic principle and the design of our ULF MRI system.