QuSpin: a Python package for dynamics and exact diagonalisation of quantum many body systems. Part II: bosons, fermions and higher spins

@article{Weinberg2019QuSpinAP,
  title={QuSpin: a Python package for dynamics and exact diagonalisation of quantum many body systems. Part II: bosons, fermions and higher spins},
  author={Phillip Weinberg and Marin Bukov},
  journal={SciPost Physics},
  year={2019}
}
We present a major update to QuSpin, SciPostPhys.2.1.003 – an open-source Python package for exact diagonalization and quantum dynamics of arbitrary boson, fermion and spin many-body systems, supporting the use of various (user-defined) symmetries in one and higher dimension and (imaginary) time evolution following a user-specified driving protocol. We explain how to use the new features of QuSpin using seven detailed examples of various complexity: (i) the transverse-field Ising chain and the… 

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References

SHOWING 1-10 OF 112 REFERENCES

QuSpin: a Python Package for Dynamics and Exact Diagonalisation of Quantum Many Body Systems part I: spin chains

We present a new open-source Python package for exact diagonalization and quantum dynamics of spin(-photon) chains, called QuSpin, supporting the use of various symmetries in 1-dimension and

Phase space representation of quantum dynamics

Observation of a many-body dynamical phase transition with a 53-qubit quantum simulator

TLDR
Here, a quantum simulator composed of up to 53 qubits is used to study non-equilibrium dynamics in the transverse-field Ising model with long-range interactions, enabling the dynamical phase transition to be probed directly and revealing computationally intractable features that rely on the long- range interactions and high connectivity between qubits.

QuTiP 2: A Python framework for the dynamics of open quantum systems

Matrix product state applications for the ALPS project

Exploring the many-body localization transition in two dimensions

TLDR
The observation of a many-body localization transition between thermal and localized phases for bosons in a two-dimensional disordered optical lattice is reported, highlighting the power of quantum simulation to solve problems that are currently inaccessible to classical computing techniques.

DiracQ: A Quantum Many-Body Physics Package

We present a software package DiracQ, for use in quantum many-body Physics. It is designed for helping with typical algebraic manipulations that arise in quantum Condensed Matter Physics and Nuclear

Many-body localization in a quantum simulator with programmable random disorder

Interacting quantum systems are expected to thermalize, but in some situations in the presence of disorder they can exist in localized states instead. This many-body localization is studied

Many-Body Delocalization in the Presence of a Quantum Bath

Closed generic quantum many-body systems may fail to thermalize under certain conditions even after long times, a phenomenon called many-body localization (MBL). Numerous studies have left no doubt

Time-dependent density-matrix renormalization-group using adaptive effective Hilbert spaces

An algorithm for the simulation of the evolution of slightly entangled quantum states has been recently proposed as a tool to study time-dependent phenomena in one-dimensional quantum systems. Its
...