Dynamic magnetic speckle
When temperature is increased more and more magnetic regions start to fluctuate, and so do the intensity fluctuations in the x-ray speckle patterns.
The speckle displayed in the movies are a zoom of the central maximum of the speckle peak shown below and is a movie of about one hour.
Still at 69 K the sample is however still largely frozen. One likes to speak of a non ergodic system.
The movies here are smoothed using bilinear interpolation to improve visibility of the speckle (diameter of ~5 pixels).
For movies that are not interpolated and keep their original pixel values click
here.
| Static speckle: 52 K | Start of dynamic speckle: 59 K |
Dynamic speckle: 69 K |
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Magnetic speckle pattern of an ultrathin holmium film |
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