Experimental considerations for the development of a nuclear magnetic resonance force microscope

The nuclear magnetic resonance force microscope is a non-invasive three dimensional imaging tool which is a great improvement over conventional NMR. A sample is attached to a mechanical silicon oscillator and placed in a large static magnetic field. The sample is magnetized by the static field, and a net magnetization in the z-direction is produced. An rf coil is placed near the sample to excite spins into resonance, and a permanent magnetic tip is placed along the direction of the static field to resolve the excited spins. From coupling the magnetization to the field gradient a force is produced on the mechanical oscillator. The motion of the mechanical oscillator is detected with a fiber optic interferometer. From the displacement of the mechanical oscillator a force map can be determined and a final three-dimensional image can be produced. An experiment on paraffin wax has demonstrated that the microscope can detect NMR from extremely small samples. The microscopic mechanical oscillators were tested for use in the NMRFM probe and their fabrication process was optimized.;Also NMR on phosphorous and deuterium was performed to determine the strength of the rf field and to determine the rf field necessary to excite protons. Some conventional NMR was done to determine the properties of yttrium in an yttrium chloride solution for the purpose of future NMRFM studies.