Heralded GHZ on Belenos

balewski · September 17, 2025, 3:05am

Hi,
I wanted to explore how much resources are needed to construct a heralded GHZ state on Belenos.
This is the circuit I run

github.com

balewski/quantumMind/blob/main/Quandela/toys/noisy_ghz_Belenos.py

#!/usr/bin/env python3
__author__ = "Jan Balewski"
__email__ = "janstar1122@gmail.com"

'''

'''
from noisy_bell import monitor_async_job

import perceval as pcvl
from perceval.algorithm import Sampler
cnotH = pcvl.catalog["heralded cnot"].build_processor()
cnotP = pcvl.catalog['postprocessed cnot'].build_processor()


#=================================
#  M A I N 
#=================================
if __name__ == "__main__":

This file has been truncated. show original

In order to see a few hundred ‘000’ and ‘111’ states I needed to issue 2e13 photons.

|0,0,0,1,2,0>: 4
  |1,0,0,0,2,0>: 6
  |1,0,1,0,1,0>: 403
  |0,1,0,2,0,0>: 11
  |0,0,1,1,1,0>: 2
  |0,0,1,1,0,1>: 13
  |0,1,0,0,0,2>: 13
  |0,2,0,1,0,0>: 3
  |0,1,0,1,0,1>: 372
  |1,0,0,1,0,1>: 25
  |0,0,2,1,0,0>: 1
  |1,0,1,0,0,1>: 22
  |0,0,1,0,2,0>: 6
 <snip>

Few questions:

is my GHZ circuit correct? I used 2 heralded CNOT gates , because I want to add more circuitry later - this is just a test.
is it feasible to run this circuit on real Belenos? How much worse will it get in terms of S/N?
what kind of plan I should purchase to be able to run this circuit on Belenos and how do I convert issued photons into the charge on my credit card?