Research Experiences for Undergraduates in Computational Methods with Applications in Materials Science
MSU Affiliation
College of Arts and Sciences; Department of Physics and Astronomy; Center for Computational Sciences
Major
Physics
Research Mentor
Rudolf Torsten Clay
Creation Date
7-27-2026
Abstract
The cuprate Sr14-x Cax Cu24 041 is the only known ladder cuprate superconductor, exhibiting a maximum superconducting transition temperature of approximately Tc=9 K under an applied pressure of 4.5 GPa. Prior to the onset of superconductivity, the material exhibits increasingly two-dimensional electronic behavior as inter-ladder coupling strengthens. Negative charge-transfer energies, are predicted to further enhance inter-ladder coupling, motivating the study of larger coupled-ladder systems. This work employs the Constrained Path Quantum Monte Carlo (CPQMC) algorithm to extend previous studies from two coupled ladders to larger ladder geometries. Simulations were performed for 2x8 ladders (32 Cu and 44 O sites; 76 total orbitals) and 4x8 ladders (64 Cu and 88 O sites; 152 total orbitals) and 4x16 ladders (128 Cu and 184 O sites; 312 total orbitals), over a range of hole dopings and charge-transfer energies. Bond orders and charge densities were calculated and compared between the Density Matrix Renormalization Group (DMRG) results and our 2x8 CPQMC calculations. Excellent agreement with DMRG validates the accuracy of CPQMC, while the larger 4x8, and 4x16 systems reproduce the trends observed in smaller ladders across the range of doping levels and charge-transfer energies studied. These results demonstrate that CPQMC provides an accurate and computationally efficient framework for investigating larger coupled-ladder systems and their evolution toward two-dimensional electronic behavior. Our results confirm the enhancement of inter-ladder coupling in the negative charge transfer regime.
Presentation Date
Summer 7-30-2026
Keywords
superconductivity, computational physics, quantum Monte Carlo
Recommended Citation
Williams, Jane Kate and Clay, Rudolf T., "Two Dimensional crossover of Cuprate Ladders" (2026). Research Experiences for Undergraduates in Computational Methods with Applications in Materials Science. 28.
https://scholarsjunction.msstate.edu/ccs-reu/28
