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Travelling waves and magnetic domain walls

It took a while but I finally figured out, after almost 3 days, as to how to visualize a travelling wave using the method I've been using so far  using ipywidgets on an ipython notebook! And here is the result of it. The first plot shows how the envelope of the pulse as a whole changes with change in the total number of modes added in phase and the second plot shows how the pulse moves along the x-direction in time. So far, I'm pretty happy with the incremental progress I've made and my resolve to build something on a solid foundation has strengthened over the last month. I will keep pushing this further, at whatever slow pace I can, adding more and more complexity to it. Let's see where the rise takes me.

Otherwise, the interesting thing today was the bi-monthly departmental colloquium, delivered this time around by Prof. Anil Kumar from IISc, Banglore. His research interests include spintronics, nano-magnetization, and spin polarized electron scattering. He talked about magnetic domain walls and domain wall re-engineering. It was one of the few talks that I've been able to follow from the beginning to the end of the talk, especially because he emphasized on the group's experimental results, the ideology behind performing a certain experiment and the various methods of data acquisition to understand said experiment.

After briefly talking about what magnetic domains are and the factors that determine the creation of magnetic domains in a material, he talked about the domain walls and their morphology. He talked about how their width depends on the amount of anisotropy in a material and on the magnetic exchange energy in the material. He showed us simulations of how the magnetization of a material changes due to an applied magnetic field over time, which is through the formation of magnetic domains at the edges of the material, which are aligned with the applied magnetic field, which then propagate through the material to meet at the center. All this assuming that our material is perfect and without impurities. Impurities act as locus for the formation of domains, which wouldn't be ideal. In the middle of the talk, he took a detour to talk about the need for research in this particular area, which has applications in high density and fast memory access. He talked about racetrack memory and how it can revolutionize computer memory as we know it. All in all, it was a brilliant talk, very approachable and easily understandable with any physics junior.

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