2026/03/31 by Cliò Efthimia Agrapidis, Satoshi Nishimoto
Physics and Astronomy · #Advanced Condensed Matter Physics #Topological Materials and Phenomena #Physics of Superconductivity and Magnetism
paper · pdf · doi:10.1103/8jr6-87ds
We study the hole-doped Kitaev-Heisenberg chain using the density-matrix renormalization group. In the Kitaev-only limit, the bond-directional exchange itself promotes pairing, favoring spin-singlet and spin-triplet superconducting tendencies for antiferromagnetic and ferromagnetic Kitaev couplings, respectively, together with finite-size Majorana edge correlations suggestive of topological superconductivity. In the full Kitaev-Heisenberg chain, cooperative <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"> <a:mi>J</a:mi> </a:math> - and <b:math xmlns:b="http://www.w3.org/1998/Math/MathML"> <b:mi>K</b:mi> </b:math> exchanges broadly stabilize superconductivity, while competition between <c:math xmlns:c="http://www.w3.org/1998/Math/MathML"> <c:mi>J</c:mi> </c:math> and <d:math xmlns:d="http://www.w3.org/1998/Math/MathML"> <d:mi>K</d:mi> </d:math> induces a strong filling dependence and enables superconductivity even when both <e:math xmlns:e="http://www.w3.org/1998/Math/MathML"> <e:mi>J</e:mi> </e:math> and <f:math xmlns:f="http://www.w3.org/1998/Math/MathML"> <f:mi>K</f:mi> </f:math> are weak. At quarter filling, this competition produces a Mott insulator with spontaneous hopping dimerization. These results identify magnetic frustration as a common mechanism underlying superconducting and interaction-driven insulating phases in doped Kitaev systems.