Synthesis of Bulk Superconducting LiNbO$_2$ Crystals through CaH$_2$ Reduction
Abstract
We have synthesized layered superconducting LiNbO crystals through a bulk phase transformation from LiNbO single crystals via CaH reduction. As the Nb valence is reduced from 5+ to 3+, the material undergoes a structural transformation to the resulting product, LiNbO, which is accompanied by metallic behavior and a superconducting transition, Tc onset, as high as 14.4 K. Secondary ion mass spectroscopy (SIMS) and X-ray photoelectron spectroscopy (XPS) show that the resulting phase is hole-doped through de-lithiation during the reduction. Magnetization and AC susceptibility measurements from a tunnel diode resonator confirm the bulk nature of superconductivity with a superconducting volume fraction of approximately 77% and an upper critical field approaching 26 T. Our study demonstrates extreme hydride reduction as an effective method to induce phase transformations with non-topotactic pathways and can be used to synthesize bulk materials with exotic properties.
Cite
@article{arxiv.2607.06819,
title = {Synthesis of Bulk Superconducting LiNbO$_2$ Crystals through CaH$_2$ Reduction},
author = {Ryan Paxson and Stephanie J. Hong and Bicky Moirangthem and Parham Kabirifar and Saya Takeuchi and Tianyu Li and Chih-Yu Lee and Haotong Liang and Keenan Avers and Kamal Joshi and Amlan Datta and Makariy Tanatar and Shanta Saha and Peter Zavalij and Ruslan Prozorov and Alexander J. Grutter and Efrain E. Rodriguez and Ichiro Takeuchi},
journal= {arXiv preprint arXiv:2607.06819},
year = {2026}
}
Comments
17 main text pages, with 5 figures. Supporting information section which is 3 pages and 3 figures