Natural Superconductivity Observed in Meteorites Above 5 K

Previous studies have shown that meteorites can contain unusual natural phases, such as quasicrystals, that have otherwise been found only in synthetic samples [1]. Because of this, meteorites are good candidates to search for natural superconductivity, which has only been found in Covellite [2]. Because natural samples are inhomogeneous and superconducting phases can be very small, we used Magnetic Field Modulated Microwave Spectroscopy (MFMMS), which can detect 10^-12 cc of superconducting material, three orders of magnitude better than Vibrating Sample Magnetometry (VSM). We measured a series of meteorites, surveying representative samples from most major categories of meteorites. In two of the meteorites, we discovered superconducting phases above 5 K using MFMMS, and verified this using VSM. We characterized these phases using Energy-dispersive X-ray spectroscopy and Inductively Coupled Plasma Mass Spectroscopy. To our knowledge, these samples are the first identification of extraterrestrial superconducting phases. They are particularly significant because these materials could be superconducting in extraterrestrial environments.
[1] L. Bindi, et al., Nature, 6 38117 (2016)
[2] F. Di Benedetto, et al., Eur J Mineral, 18 283 (2006)