name: mxl-driver-qutip
description: This skill should be used when users want to run the QuTiP molecular driver (preset TLS or custom Hamiltonians) in MaxwellLink and need correct parameter passing for socket or embedded mode.

QuTiP driver (model Hamiltonians)

Confirm prerequisites

• Ensure qutip is installed in the driver environment; import failures are expected otherwise.

Use preset TLS mode

• Prefer passing TLS parameters as top-level tokens to avoid comma-parsing confusion:
• Socket: mxl_driver --model qutip --port <port> --param "preset=tls, omega=0.242, mu12=187, orientation=2, pe_initial=1e-4"
• Embedded: Molecule(driver="qutip", driver_kwargs={"preset": "tls", "omega": 0.242, "mu12": 187, "orientation": 2, "pe_initial": 1e-4})

Use custom-module mode

• Provide a Python file that defines build_model(**kwargs) and returns H0, mu_ops, optional c_ops, and optional rho0.
• Socket (module next to the job): mxl_driver --model qutip --port <port> --param "preset=custom, module=hcn_qutip.py"
• Socket (absolute path): mxl_driver --model qutip --port <port> --param "preset=custom, module=/abs/path/spec.py"
• Embedded: Molecule(driver="qutip", driver_kwargs={"preset": "custom", "module": "hcn_qutip.py"})
• Ensure the driver process can import the module:
  • Launch the driver from the directory that contains the module, or
  • Add that directory to PYTHONPATH, or
  • Use an absolute module=... path on shared filesystem.

Notes

• Use fd_dmudt=true only when an analytical dipole-current expression is unavailable or unstable.
• For example setups, compare to tests/test_qutip/ and docs/source/drivers/qutip.rst.