dannygoodacre / magpy

Magnus based time-integration for spins and qubits under a magnetic field

Magnus based time-integration for qubits under a magnetic field.

Installation

MagPy may be installed via pip:

pip install magpy

To build from source:

1. Clone this repository

2. Install the base requirements

3. Run python3 -m build . from the root directory

magpy's Issues

Finalise str and repr for core objects

The three objects

• PauliString
• HamiltonianOperator
• FunctionProduct

require their str and repr functions to be finalised.

Current issues:

• incorrect order of tensors and functions
• incorrect display of PauliStrings when an HOp has multiple qubits

Fix unit tests

The entire unit test suite is out of date. It needs to be updated to match recent changes.

Add tensor support to core objects

The core objects currently only support scalar coefficients. Adding tensor coefficient support allows for easy batching of systems.

For example H = tensor(1,2)*X + sin*Y is a parallel system of H1 = X + sin*Y and H2 = 2*X +sin*Y.

Scalar-valued functions will distribute across the batch, and vector-valued functions must agree with the batch's length. For now, we will not support batching vector-valued functions, e.g. distributing repeating a 2-wide function across a 4-wide batch.

Update notebooks

Update notebooks to include new batching features

Magnus expansion with batching

Add support for evaluating the Magnus expansion of the new batched Hamiltonian operators.

Given a Hamiltonian with a batch size k and n qubits and a list of m intervals, then we return a tensor with shape (m, k, n, n).