Hi Jan,
two things:
- Because you have shots taken in one basis you can only access the diagonal part of the density matrix so having a method to measure the energy at an abitrary times, but you can measure the energy at the end of the evolution
- There is currently no implementation for energy at the end of the evolution implemented in the braket sdk. I would encourage you to submit a github issue to ask for them to potentially implement this.
Best,
Phil