# Lanczos steps to improve variational wave functions

@article{Becca2014LanczosST, title={Lanczos steps to improve variational wave functions}, author={Federico Becca and Wenjun Hu and Yasir Iqbal and Alberto Parola and Didier Poilblanc and Sandro Sorella}, journal={arXiv: Strongly Correlated Electrons}, year={2014} }

Gutzwiller-projected fermionic states can be efficiently implemented within quantum Monte Carlo calculations to define extremely accurate variational wave functions for Heisenberg models on frustrated two-dimensional lattices, not only for the ground state but also for low-energy excitations. The application of few Lanczos steps on top of these states further improves their accuracy, allowing calculations on large clusters. In addition, by computing both the energy and its variance, it is…

## 7 Citations

Emergent Phases of Quantum Matter in Strongly Correlated Mott Insulators

- Physics
- 2018

Author(s): Iaconis, Jason John | Advisor(s): Balents, Leon | Abstract: Strongly correlated electron systems have the potential to host very exoticphases of matter. In order to have relevance to real…

Spin Liquid versus Spin Orbit Coupling on the Triangular Lattice

- Physics
- 2017

In this paper, we explore the relationship between strong spin-orbit coupling and spin liquid physics. We study a very general model on the triangular lattice where spin-orbit coupling leads to the…

Spin liquid nature in the Heisenberg J1-J2 triangular antiferromagnet

- Physics
- 2016

We investigate the spin-$\frac{1}{2}$ Heisenberg model on the triangular lattice in the presence of nearest-neighbor $J_1$ and next-nearest-neighbor $J_2$ antiferromagnetic couplings. Motivated by…

Quantum and Classical Phases of the Pyrochlore Heisenberg Model with Competing Interactions

- PhysicsPhysical Review X
- 2019

We investigate the quantum Heisenberg model on the pyrochlore lattice for a generic spin-$S$ in the presence of nearest-neighbor $J_{1}$ and second-nearest-neighbor $J_{2}$ exchange interactions. By…

Persistence of the gapless spin liquid in the breathing kagome Heisenberg antiferromagnet

- Physics
- 2018

The nature of the ground state of the spin $S=1/2$ Heisenberg antiferromagnet on the kagome lattice with breathing anisotropy (i.e., with different superexchange couplings $J_{\vartriangle}$ and…

Pinwheel valence bond crystal ground state of the spin-
12
Heisenberg antiferromagnet on the shuriken lattice

- PhysicsPhysical Review B
- 2021

Nikita Astrakhantsev, 2, ∗ Francesco Ferrari, ∗ Nils Niggemann, ∗ Tobias Müller, Aishwarya Chauhan, Augustine Kshetrimayum, 7 Pratyay Ghosh, Nicolas Regnault, Ronny Thomale, 6 Johannes Reuther, 7…

Quantum State Complexity in Computationally Tractable Quantum Circuits

- Physics, Computer SciencePRX Quantum
- 2021

It is argued that automaton wave functions have high quantum state complexity, and evidence of a linear growth of design complexity in local quantum circuits is presented, consistent with conjectures from quantum information theory.

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