# grape_coop.m

Pairs of cooperative pulses that may be used as components of a phase cycle. The pulses are designed to produce as much of the destination state as they can, and to have impurities of opposite sign. Adding the outcomes of the two experiments then destroys the impurities.

## Syntax

    [traj_data,fidelity,gradient]=grape_coop(phi_profile,spin_system)


## Arguments

    phi_profile  -  phase profiles of the two pulses,
concatenated horizontally


## Outputs

     traj_data    -  trajectory information structure

fidelity     -  cooperative fidelity measure



## Examples

An example of a cooperative optimisation is available in examples/optimal_control/cooperative/state_transfer_coop.m file.

## Notes

Only phase-modulated point-to-point transformations are supported.