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Cake day: July 27th, 2023

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  • Altermagnets are pretty interesting because their most defining feature is not the magnetic order in the materials. They look like ordinary antiferromagnets where the spins of adjacent atoms point in opposite direction and compensate each other, so no large magnetic fields are created. What differentiate altermagnets from antiferromagnets is how the electrons with different spin behave. When pulling current through altermagnets it will consist of purely spin up electrons along one crystal axis and purely spin down along orthogonal crystal axes. Thus the spin currents have a ‘alternating’ pattern, giving the name altermagnet. This is primarily exciting for the field of ‘spintronics’ which is all about creating technologies using spin currents.

    Not all altermagnets are equally interesting, many antiferromagnets can be reclassified to altermagnets but they are generally insulating. (fun fact the first ever measured and textbook antiferromaget MnF2 is actually altermagnetic) So materials discovery of new altermagnets is important to find metallic, semi-metallic or even super conducting altermagnets.





  • While in not in the field either, I do know that it is quite unusual in computer science academics to publish in actual peer reviewed journals. This is because it can be a long process, and the field is very fast moving, so your results would be outdated by the time you publish. Thus, a paper is typically synonymous with a conference proceeding, and can be found on arxiv. I found this Paper on the arxiv from 2017/2018 which seems to be when this paper was originally published for the scientific community and presented at a very “good” (if I had to guess) conference. Google scholar says this paper has 650 citations, so it probably has had quite some impact. However, I would guess this method is well known and is already implemented in many models, if it was truly disruptive.


  • The article linked here is rubbish, CrSBr is not a meta material and also not a superconductor. It is a layered semiconductor. However, the Nature article they link to is quite interesting. The background is in cavity engineering, which is where one tries to modify intrinsic material properties by coupling to light “strongly”. This is usually done by creating a cavity (think two opposing mirrors around the material) and have light bounce back and forth.

    Here instead they don’t need to use mirrors, but the refractive index is different enough to trap light in the material, and the electronic properties seem to be quite sensitive to the light because the magnetic phase is sensitive to magnetic fields and the different magnetic phases have quite different electronic properties. So all in all they find a strong light-matter coupling but only below 132K (the critical temperature of the magnetic phase).