Two-hole ground state wavefunction: Non-BCS pairing in a t − J two-leg ladder

Superconductivity is usually described in the framework of the Bardeen-Cooper-Schrieffer (BCS) wavefunction, which even includes the resonating-valence-bond (RVB) wavefunction proposed for the high-temperature superconductivity in the cuprate. A natural question is if any fundamental physics could b...

Full description

Saved in:
Bibliographic Details
Published in:Physical review. B 2018-12, Vol.98 (24), p.1, Article 245138
Main Authors: Chen, Shuai, Zhu, Zheng, Weng, Zheng-Yu
Format: Article
Language:English
Subjects:
Antiferromagnetism
Computer simulation
Correlation analysis
Ground state
High temperature
Superconductivity
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Superconductivity is usually described in the framework of the Bardeen-Cooper-Schrieffer (BCS) wavefunction, which even includes the resonating-valence-bond (RVB) wavefunction proposed for the high-temperature superconductivity in the cuprate. A natural question is if any fundamental physics could be possibly missed by applying such a scheme to strongly correlated systems. Here we study the pairing wavefunction of two holes injected into a Mott insulator/antiferromagnet in a two-leg ladder using variational Monte Carlo approach. By comparing with density-matrix renormalization group (DMRG) calculation, we show that a conventional BCS or RVB pairing of the doped holes makes qualitatively wrong predictions and is incompatible with the fundamental pairing force in the t− J model, which is kinetic-energy driven by nature. By contrast, a non-BCS-like wavefunction incorporating such novel effect will result in a substantially enhanced pairing strength and improved ground state energy as compared to the DMRG results. We argue that the non-BCS form of such a new ground state wavefunction is essential to describe a doped Mott antiferromagnet at finite doping.
ISSN:2469-9950
2469-9969
DOI:10.1103/PhysRevB.98.245138