It is and it isn't. It's at ambient pressure (which is something useful), and there is something very odd happening much higher up that needs to be explained. They say their sample purity is higher than the one the Korean team had, so that would normally lead to better yield and easier confirmation of the superconductivity. But since it does show the Meissner effect in other samples as well at room temperature there is a lot that still needs explaining before we can say it is a failed reproduction.

perhaps an impurity caused the effect they're looking for

Yes, that's possible and something that has already happened once before: this is exactly how x-rays and eventually radioactivity were discovered, a chance contamination.

I adore stories that include the phrase "that's odd" or "something odd happens when ..."

Even if we don't get the astonishing result originally claimed by the rogue paper, it's still a triumph of science in my ignorant opinion.

And sometimes 'that's odd' leads to things larger than the original goal. You really don't want to hear those words in the doctors' office though.

Tc = 110 K would take the #4 spot on https://en.wikipedia.org/wiki/List_of_superconductors

#3 spot at atmospheric pressure

At atmospheric pressure, no less.

> HgTlBaCaCuO

New band name. And band gap.

One of the most well known, YBCO, has a Tc of 95K.

technically a failure, but still a strange result

I don't think it's a failure if the original claims are showing some kind of promise, science is being done, and the frontiers of knowledge are being pushed forward.

In other words, not "Eureka!" but "that's weird".

Yeah it looks to me like either a replication failure or even evidence AGAINST a superconducting phase. A superconductor's resistance curve is supposed to show a sharp drop to zero at the transition temperature. If it's a dirty inhomogenous sample (e.g. specks of superconductor embedded in non-superconducting material), you get a kink where the curve descends to a non-zero background resistance. In the Southeast University data, there's a smooth curve that goes down until they get to the noise floor. There's no transition.