New microscope reveals nanoscale details

August 9, 2011

An X-ray scanning measurement. Diffraction patterns are recorded in the far-field by an X-ray area detector by scanning the sample, depicted as the overlapping white, blue, and red circles (credit: Ashish Tripathi et al./PNAS)

Physicists at the University of California, San Diego have developed an X-ray microscope that can penetrate deep within materials and see minute details at the scale of a single nanometer.

They developed an algorithm that is able to convert the diffraction patterns produced by X-rays bouncing off the nanoscale structures into resolvable images. To test their microscope’s ability to penetrate and resolve details at the nanoscale, the physicists made a layered film composed of the elements gadolinium and iron. Such films are now being studied in the information technology industry to develop higher-capacity, smaller, and faster computer memory and disk drives.

Under the X-ray microscope, the layered gadolinium and iron film crinkles up magnetically to form a series of magnetic domains, which appear like the repeating swirls of the ridges in fingerprints. Being able to resolve those domains at the nanoscale for the first time is critically important for computer engineers seeking to cram more data into smaller and smaller hard drives.

Gadolinium spin density reconstructions on the magnetic hysteresis curve while decreasing the external field. Phase is encoded as hue and magnitude is encoded as brightness. (Credit: Ashish Tripathia et al./PNAS)

One immediate application of this lens-less X-ray microscope is the development of smaller data-storage devices for computers that can hold more memory, the scientists said.

Ref.: Ashish Tripathi, et al., Dichroic coherent diffractive imaging, PNAS, August 8, 2011 [DOI: 10.1073/pnas.1104304108]