Demo on measurement-based quantum computation

[soosub]

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Title: Measurement-based quantum computation

Summary: A demo on measurement-based quantum computation

Relevant references:

• https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.86.5188
• https://quantum-journal.org/papers/q-2021-02-04-392/

Possible Drawbacks: None

Related GitHub Issues: None

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• Pull Request ID: 485
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[soosub]

Some additional resources:

• https://phas.ubc.ca/~raussen/Supplements/VideoLectures.html
• https://arxiv.org/pdf/1711.04921.pdf

[soosub]

@radras we could consider using FlamingPy to visualize cluster states. In particular, in the fault tolerant section where we need 3D cluster states 👀 If yes, we should add it to the requirements.txt (or whatever they have here)

[soosub]

@KetpuntoG or @CatalinaAlbornoz, can one of you add @isschoch and @mauriceweber as reviewers here?

[isschoch]

Cannot wait to learn some cool stuff about MBQC!

[KetpuntoG]

Hey! I cannot pass on the review to the next person until you complete the TODO's Can you take a look at them? 🙂

[soosub]

We're working on it @KetpuntoG 😌

[soosub]

Hey it's ready for another review. I have one questions about formatting though:

• Can I combine references into one pair of brackets? I have a couple of places where we reference multiple papers but it comes out as [1] [2] [3]. It would be nice to have something like [1, 2, 3] as per usual.

[KetpuntoG]

Hey it's ready for another review. I have one questions about formatting though:

• Can I combine references into one pair of brackets? I have a couple of places where we reference multiple papers but it comes out as [1] [2] [3]. It would be nice to have something like [1, 2, 3] as per usual.

Thanks! Not to my knowledge. It is something that appears in other demos. If I find out, I'll let you know 👌

[soosub]

Ready for another review @KetpuntoG

[soosub]

For the dual/primal plot I used this:

from flamingpy.codes import SurfaceCode
from plotly.subplots import make_subplots
import plotly.graph_objects as go

# RHG lattice
RHG = SurfaceCode(3)

# Layout
size = 450
fig = make_subplots(rows=1, cols=2, 
                    specs=[[{'type':'scene'}, {'type':'scene'}]], 
                    column_titles=["Primal", "Dual"], 
                    horizontal_spacing = 0.02)
fig.update_layout(width=1.75*size, height=size)

# Primal
z = 3
fig1 = RHG.draw(backend="plotly", label=["type"], showbackground=True, width=size, height=size)
fig.update_layout(scene = dict(zaxis = {'nticks': 2, 'range': [z-0.5, z+0.5], 'dtick':1, "showspikes":False}), showlegend=False)
fig.update_layout(scene = dict(xaxis = {'dtick':1, "showspikes":False}))
fig.update_layout(scene = dict(yaxis = {'dtick':1, "showspikes":False}))
fig.add_trace(fig1.data[0], row=1, col=1)
fig.add_trace(fig1.data[1], row=1, col=1)

# Dual
z = 2
fig2 = RHG.draw(backend="plotly", label=["type"], showbackground=True, width=size, height=size)
fig.get_subplot(1,2)['zaxis'].update({'nticks': 2, 'range': [z-0.5, z+0.5], "showspikes":False})
fig.get_subplot(1,2)['xaxis'].update({'dtick':1, "showspikes":False})
fig.get_subplot(1,2)['yaxis'].update({'dtick':1, "showspikes":False})
fig.add_trace(fig2.data[0], row=1, col=2)
fig.add_trace(fig2.data[1], row=1, col=2)

# Showing figure
fig.show(width=size, height=size)

# Saving figure
fig.write_image("primal_dual.jpeg")
fig.write_html("primal_dual.html")

[soosub]

@KetpuntoG @isaacdevlugt I addressed all the comments. There are little things that @radras might want to address still, but I don't think they are strictly necessary. We could always update the demo in the future. I will leave the finalisation in your capable hands 👍🏼

[KetpuntoG]

Don't worry about updating the branch @soosub , the demo is perfect 😄 when we upload it we will update everything

[soosub]

@KetpuntoG I was planning to address this now the FlamingPy August release is out but there seem to be some issues 🥵

[KetpuntoG]

@KetpuntoG I was planning to address this now the FlamingPy August release is out but there seem to be some issues 🥵

Ah okey! Let's see if Narinam answer you :)

[KetpuntoG]

@soosub , @radras thanks for this great demo! Tomorrow we will announce the release of this demo on Pennylane twitter 🚀