Input Fock state |1,0> not accepted in a calculation on a QPU

Hello Perceval Team,

I am struggling with a calculation on the QPU that seems not accept input Fock states of the type |1,0>. The error i obtain is "“RuntimeError: Not enough photons in input state (1 < 2)”. The same calculation runs successfully on “sim:ascella”. In the next screen-shots n = 1.


This limitation has been set because of hardware limitation. It can be found in the documentation of Ascella, on the cloud.

Due to hardware change, this limitation should be set to 1 photon in the next days, so check regularly.

Thanks for using Perceval,

Hello Aurélien,

Thank you very much for your answer. Did i understand correctly: for the moment calculations with Fock states |1,0> (1 photon on the first spatial mode) are not possible due to hardware limitations ?


Hello Aleksandrina,

Sorry for the delay of the answer.
One photon sampling was prevented by a software constraint we had set in front of the hardware. However, this limitation has now been lifted for a week. So you can now perform |1,0> computations.

Best wishes,