TY - JOUR
T1 - Field-induced superconductivity near the superconducting critical pressure in UTe2
AU - Aoki, Dai
AU - Kimata, Motoi
AU - Sato, Yoshiki J.
AU - Knebel, Georg
AU - Honda, Fuminori
AU - Nakamura, Ai
AU - Li, Dexin
AU - Homma, Yoshiya
AU - Shimizu, Yusei
AU - Knafo, William
AU - Braithwaite, Daniel
AU - Valiŝka, Michal
AU - Pourret, Alexandre
AU - Brison, Jean Pascal
AU - Flouquet, Jacques
N1 - Funding Information:
Acknowledgements We thank K. Miyake, A. Miyake, H. Harima, K. Machida, Y. Yanase, V. Mineev, S. Fujimoto, K. Ishida, Y. Tokunaga, and F. Hardy for fruitful discussion. This work was supported by ERC starting grant (NewHeavyFermion), ANR (FRESCO) and KAKENHI (JP19H00646, JP20K20889, JP20H00130, JP20KK0061), GIMRT (20H0406), and ICC-IMR.
Publisher Copyright:
© 2021 The Physical Society of Japan.
PY - 2021/7/1
Y1 - 2021/7/1
N2 - We report the magnetoresistance under pressure in the novel spin-triplet superconductor UTe2 close to the critical pressure Pc, where the superconducting phase terminates, for field along the three a, b, and c-axes in the orthorhombic structure. The superconducting phase for H || a-axis just below Pc shows a field-reentrant behavior due to the competition with the emergence of magnetic order at low fields. The upper critical field Hc2 for H || c-axis shows a quasi-vertical increase in the H-T phase diagram just below Pc, indicating that superconductivity is reinforced by the strong fluctuations which persist even at high fields above 20 T. Increasing pressure leads to the disappearance of superconductivity at zero field with the emergence of magnetic order. Surprisingly, field-induced superconductivity is observed at high fields, where a spin-polarized state is realized due to the suppression of the magnetic ordered phases; the spin-polarized state is favorable for superconductivity, whereas the magnetic ordered phase at low field seems to be unfavorable. The huge Hc2 in the spin-polarized state seems to imply a spin-triplet state. Contrary to the a- and c-axes, no field-reinforcement of superconductivity occurs for magnetic field along the b-axis. We compare the results with the field-reentrant superconductivity above the metamagnetic field, Hm for the field direction tilted by ~30 deg from b to caxis at ambient pressure as well as the field-reentrant (-reinforced) superconductivity in ferromagnetic superconductors, URhGe and UCoGe.
AB - We report the magnetoresistance under pressure in the novel spin-triplet superconductor UTe2 close to the critical pressure Pc, where the superconducting phase terminates, for field along the three a, b, and c-axes in the orthorhombic structure. The superconducting phase for H || a-axis just below Pc shows a field-reentrant behavior due to the competition with the emergence of magnetic order at low fields. The upper critical field Hc2 for H || c-axis shows a quasi-vertical increase in the H-T phase diagram just below Pc, indicating that superconductivity is reinforced by the strong fluctuations which persist even at high fields above 20 T. Increasing pressure leads to the disappearance of superconductivity at zero field with the emergence of magnetic order. Surprisingly, field-induced superconductivity is observed at high fields, where a spin-polarized state is realized due to the suppression of the magnetic ordered phases; the spin-polarized state is favorable for superconductivity, whereas the magnetic ordered phase at low field seems to be unfavorable. The huge Hc2 in the spin-polarized state seems to imply a spin-triplet state. Contrary to the a- and c-axes, no field-reinforcement of superconductivity occurs for magnetic field along the b-axis. We compare the results with the field-reentrant superconductivity above the metamagnetic field, Hm for the field direction tilted by ~30 deg from b to caxis at ambient pressure as well as the field-reentrant (-reinforced) superconductivity in ferromagnetic superconductors, URhGe and UCoGe.
UR - http://www.scopus.com/inward/record.url?scp=85107982433&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85107982433&partnerID=8YFLogxK
U2 - 10.7566/JPSJ.90.074705
DO - 10.7566/JPSJ.90.074705
M3 - Article
AN - SCOPUS:85107982433
VL - 90
JO - Journal of the Physical Society of Japan
JF - Journal of the Physical Society of Japan
SN - 0031-9015
IS - 7
M1 - 074705
ER -