- IBM Research - Almaden Science Colloquium Series
- NanoMRI and the Quest for a Molecular Structure Microscope
- Nanoscale Science
Daniel Rugar is currently Manager of Nanoscale Studies in the IBM Research Division, and a Consulting Professor of Applied Physics at Stanford University. Dr. Rugar has a long history of contributions to the field of scanning microscopy. He began his work in microscopy as a Ph.D. student in Applied Physics at Stanford University, where he developed a gigahertz frequency scanning acoustic microscope operating in superfluid helium with nanometer spatial resolution. After joining IBM in 1984, he made many contributions to the development of atomic force microscopy (AFM), especially for imaging magnetic materials and for applications to data storage. His early work on magnetic force microscopy helped establish this technique as a standard tool in the magnetic recording industry. He is co-inventor of the thermo-mechanical recording technique that is the basis of the IBM "Millipede" storage device, allowing data densities up to 1 Terabit per square inch using nanoscopic indentations in a polymer recording medium.
Dr. Rugar pioneered the development of ultrathin single-crystal silicon cantilevers for ultrasensitive force detection. With his IBM colleague, John Mamin, he has set a series of records for detection of ultrasmall forces, including the current record of 800 zeptonewtons in a 1 Hertz bandwidth. Many applications followed, including ultrasensitive magnetometry of nanomagnets, discovery of long range non-contact friction effects, and development of a mechanical parametric amplifier capable of “squeezing” cantilever Brownian motion.
In 1992, he became inspired by the possibility of combining magnetic resonance imaging (MRI) with ultrasensitive force detection to overcome the traditional sensitivity limitations of MRI. The overall goal of this work is to develop a technique for imaging the three-dimensional atomic structure of biomolecules. He made the first demonstrations of magnetic resonance force microscopy (MRFM) in 1992 and has worked to improve its sensitivity and spatial resolution ever since. MRFM has developed into an exquisitely sensitive method for detection of electron spin resonance, nuclear magnetic resonance and ferromagnetic resonance. After improving the sensitivity by 7 orders of magnitude, this work reached a key milestone in 2004: the manipulation and detection of an individual electron spin. This result was called the “Top Physics Story” for 2004 by the American Institute of Physics. In recent nuclear spin experiments, Dr. Rugar’s research group has demonstrated magnetic resonance imaging with 4 nm spatial resolution, representing a volume sensitivity that is 100 million times better than the best conventional MRI microscopy. This has allowed MRI to be extended to the nanometer scale for the first time.
Dr. Rugar is also exploring nitrogen-vacancy centers in diamond for use as atomic size magnetometers. Recently his group has shown that individual NV centers can detect nuclear magnetic resonance signals from an organic sample located on the surface of the diamond.
Dr. Rugar has published over 120 scientific papers and holds 19 patents. In 2010 he was co-recipient of the Gunther Laukien Prize for his development of magnetic resonance force microscopy. He was awarded the Cozzarelli Prize from the Proceedings of the National Acacademy of Sciences for his 2009 paper on nanoscale magnetic resonance imaging. He was the 1999-2000 Distinguished Lecturer of the IEEE Magnetic Society. He received the 2004 Scientific American 50 award for research leadership in the field of imaging and the 2005 World Technology Award for Materials. He has also received IBM internal awards for contributions to scanning probe microscopy, near field optical data storage, single spin detection and nanoMRI. He is a fellow of the American Physical Society (APS), the American Association for the Advancement of Science (AAAS) and the Institute of Electrical and Electronic Engineers (IEEE).
Here is a link to the NanoMRI project page:
Link to the NanoMRI paper published in the Proceedings of the National Academy of Sciences:
The NanoMRI paper was accompanied by an IBM press release:
In previous work, IBM also
demonstrated that MRFM is sensitive enough to detect the magnetism of a single electron spin.