Superconducting valence bond fluid in lightly doped eight-leg <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:mi>t</mml:mi><mml:mtext>−</mml:mtext><mml:mi>J</mml:mi></mml:mrow></mml:math> cylinders
Hong‐Chen Jiang, Steven A. Kivelson, Dung‐Hai Lee
Abstract
Superconductivity in doped quantum paramagnets has been a subject of long theoretical inquiry. In this work, we report a density matrix renormalization group study of lightly doped $t\text{\ensuremath{-}}J$ models on the finite-width square lattice (doped hole densities $\ensuremath{\delta}=1/12$ and 1/8) with parameters for which previous studies have suggested that the undoped system in 2D is either a quantum spin liquid or a valence bond crystal. Our studies are performed on cylinders with width up to 8. Ground-state correlations are found to be nearly identical for the ``doped quantum spin liquid'' and ``doped valence bond crystal.'' Upon increasing the cylinder widths from 4 to 8, we observed a significant strengthening of the quasi-long-range superconducting correlations and a dramatic suppression of any ``competing'' charge density wave order. Extrapolating from the observed behavior of the width eight cylinders, we speculate that the system has a nodeless $d$-wave superconducting ground state in the 2D limit.