Faithin Omaha eBook Collection

Download or read book Design and Development of a Magnetic Resonance Force Microscope that Operates in Air written by Jayanth Gobbalipur Ranganath and published by . This book was released on 2004 with total page 246 pages. Available in PDF, EPUB and Kindle. Book excerpt: Magnetic Resonance Force Microscopy (MRFM) is a new and rapidly developing technology that integrates the high-sensitivity of Atomic Force Microscopy with subsurface imaging capability of Magnetic Resonance Imaging. A micro-mechanical cantilever is used to detect force signals originating from magnetic resonance within a sample. While sub-micron resolution has been achieved in certain samples, and single electron-spin sensitivity has been demonstrated, all existing setups operate in vacuum and many at cryogenic temperatures. From the point-of-view of engineering, it would be an important step to improve the resolution so that the instrument can be operated in air and to explore useful samples that can be imaged thus. In this research, a Magnetic Resonance Force Microscope is designed and developed with the intention of being operated in air. Calculations are made to demonstrate its feasibility. It necessitates implementing a high-resolution, compact and easy-to-use motion sensor, and designing suitable electronics to improve the force-sensitivity of the detector. The achieved force sensitivity (~ 10-15 N / vHz) is comparable to the thermal-noise limited sensitivity at room temperature and pressure. The developed sensor also possesses potential applications outside MRFM. For MRFM, this sensor is integrated with the other key-elements of the microscope, including a micro-wave exciter and an electromagnet. The microwave exciter is used to excite a paramagnetic sample that would be imaged. The electromagnet applies a background field. This serves to increase the signal strength. A preliminary experiment is conducted and the problems encountered are discussed.