Provide cuQuantum's cuDensityMat as a backend for QuTiP.
This backend is specifically designed for simulating large, composite quantum systems by performing tensor network contractions on the GPU.
qutip-cuquantum is available on pypi.
pip install -U qutip>=5.2.1
pip install qutip-cuquantum
It require cuquantum to be installed at runtime. If you have cuda already installed, you can install dependencies with:
pip install qutip-cuquantum[cuda11]
or
pip install qutip-cuquantum[cuda12]
If it does not work, you may need to install cuQuantum yourself, see nvidia's documentation for installation instruction.
In simple case, simply calling set_as_default before a qutip script should be sufficient to use the backend common solver:
import qutip_cuquantum
from cuquantum.densitymat import WorkStream
qutip_cuquantum.set_as_default(WorkStream())
qutip-cuquantum work well to speed-up large simulation using mesolve or sesolve.
However this backend is not compatible with advanced qutip solvers (brmesolve, HEOM) and other various feature.