Abstract
Majorana zero modes form as intrinsic defects in an odd-orbital one-dimensional superconductor, thus motivating the search for such materials in the pursuit of Majorana physics. Here, we present combined experimental results and first-principles calculations which suggest that quasi-one-dimensional K2Cr3As3 may be such a superconductor. Using inelastic neutron scattering we probe the dynamic spin susceptibilities of K2Cr3As3 and K2Mo3As3 and show the presence of antiferromagnetic spin fluctuations in both compounds. Below the superconducting transition, these fluctuations gap in K2Mo3As3 but not in K2Cr3As3. Using first-principles calculations, we show that these fluctuations likely arise from nesting on one-dimensional features of the Fermi surface. Considering these results we propose that while K2Mo3As3 is a conventional superconductor, K2Cr3As3 is likely a spin triplet, and consequently a topological superconductor.
| Original language | English |
|---|---|
| Article number | L180504 |
| Journal | Physical Review B |
| Volume | 107 |
| Issue number | 18 |
| DOIs | |
| State | Published - May 1 2023 |
Funding
ORNL is managed by UT-Battelle, LLC under Contract No. DE-AC05-00OR22725 for the U.S. Department of Energy. The U.S. Government retains and the publisher, by accepting the article for publication, acknowledges that the U.S. Government retains a nonexclusive, paid-up, irrevocable, world-wide license to publish or reproduce the published form of this manuscript, or allow others to do so, for U.S. Government purposes. The Department of Energy will provide public access to these results of federally sponsored research in accordance with the DOE Public Access Plan . The authors thank Cristian Batista for helpful conversations pertaining to the significance of the gap in . The part of the research that was conducted at ORNL's High Flux Isotope Reactor was sponsored by the Scientific User Facilities Division, Office of Basic Energy Sciences, U.S. Department of Energy. The research is partly supported by the U.S. Department of Energy (DOE), Office of Science, Basic Energy Sciences (BES), Materials Science and Engineering Division. Work at the University of Missouri is supported by the U.S. DOE, BES, Award No. DE-SC0019114. The part of this work performed at the University of Texas at Dallas is supported by U.S. Air Force Office of Scientific Research (FA9550-19-1-0037) and National Science Foundation (DMR 1921581). The contribution performed at the Air Force Research Laboratory was supported by the U.S. Air Force Office of Scientific Research (AFOSR) LRIR 18RQCOR100 as well as AOARD-MOST Grant No. F4GGA21207H002.
| Funders | Funder number |
|---|---|
| AOARD-MOST | F4GGA21207H002 |
| LRIR | 18RQCOR100 |
| Scientific User Facilities Division | |
| National Science Foundation | DMR 1921581 |
| U.S. Department of Energy | DE-SC0019114 |
| Air Force Office of Scientific Research | FA9550-19-1-0037 |
| Office of Science | |
| Basic Energy Sciences | |
| Oak Ridge National Laboratory | |
| Division of Materials Sciences and Engineering | |
| UT-Battelle | DE-AC05-00OR22725 |