Charge Fluctuation at a Quantum Critical Point.

This is a fascinating paper[1] (which I'll be reading more of in the next several weeks). But for now, I'll just highlight it here.

The authors found that charge fluctuation in a "strange metal" antiferromagnetic compound exhibit a scaling of f/T (frequency over temperature) in the optical conductivity, which often indicates the presence of a quantum critical point.

If anyone has done MBE before, you'll know how tedious and difficult it is to synthesize a material such as this, and have it be pristine enough to produce these effects that can be measured, at a THz level, no less!

There are many implications here, not the least of which is that the cuprate high-Tc superconductors share the same "parent" or undoped state, being antiferromagnetic perovskites themselves. There have been experiments indicating that the cuprates superconductors are also influenced by their proximity to a quantum critical point.

This is another example where some of the most fundamental aspects of quantum mechanics, in this case the concept of quantum criticality, can often be clearly manifested in a condensed matter system, not in elementary particle physics experiment.

Zz.

[1] L. Prochaska et al., "Singular charge fluctuations at a magnetic quantum critical point." Science v.367, p.285 (2020). ArXiv version of the paper can be found here.

What Really Happened At The Big Bang?

Don't you want to know?

Here is a simplified explanation of what the Big Bang is, and what the Big Bang is NOT!



Zz.

Thirteen tips for engaging with physicists, as told by a biologist

This is a rather fun reading, and it has a bit of truth if we (physicists) do a bit of self-reflecting on how we operate.

I think I'm going to post the link to the LMS for the general physics course I'll be teaching this Spring for Life Science/Pre-Med majors. 😄

And then there's a reverse flow, where you get 12 tips for engaging with biologist, as told by a physicist. Even a lot more self-reflection there!

In the end, biologists and physicists gain a lot from talking to each other.

And oh, Happy New Decade, btw!

Zz.