Emulation and results

Once the pulse shaping setup is complete, one can launch the emulation to actually get results from the computation. Two types of emulation are available in Pulser Studio:

• Local: small-scale emulation running entirely in the user’s browser ;
• Cloud: sending the experiment to one of Pasqal’s large-scale emulators.

Local emulation

The Local emulation tab allows small-scale implementations to be run directly in the Pulser Studio web application, through an emulator built for a web browser.

Limitations

Important

Due to the limited processing power of a browser-based emulator, local emulation is limited to experiments with registers up to 12 qubits.

The local emulation behavior will depend on the size of the register. Up to 6 qubits, this emulation is instantaneous. From 6 to 12 qubits, the emulation time will depend on the complexity of the experiment.

Up to 6 atoms

The emulation is automatic and instantaneous.

Up to 12 atoms

The emulation has to be started explicitely and will display its progress while running.

More than 12 atoms

The local emulation is disabled.

Measure and results

When using the local emulation, we have access to intermediate measures at all times during the execution of the sequence.

Note

This would not be the case for an execution with the real Pasqal hardware, as any measure of the state of the register makes it lose its quantum properties.

Using the Play of the Local emulation panel, you can simulate the execution of the sequence at a human-perceivable speed. The current time will be visualized on the pulse timeline as a yellow bar.

The vertical yellow bar shows where we are in the sequence execution.

During the execution of the experiment, laser pulses will be shown as gradual highlights on the register, symbolizing an analog computation mode where we are interacting with all the atoms at the same time (for global channels) or on specific atom targets (for local channels).

At any given time, a single quantum state may be highlighted to gain a better understanding of the excitation of the atoms. The ∣0⟩ state is represented by a smaller circle, corresponding to a ground state energy level of the atom, while a measured ∣1⟩ is captured by a larger circle, corresponding to a Rydberg-type excitation of the atom.

Hovering the cursor over a quantum state to highlight the excitation level of the atoms from that particular measurement.

Based on the user’s preferences, both histograms and quantum state composition can be visualized to gain a better understanding of the probability distribution of the quantum solution.

Visualizing intermediate quantum states for an execution both for histogram (left) and quantum state view (right).

Note for advanced users

As one can see, the whole quantum processing usually takes less than 10 microseconds (including letting the system reach an equilibrium state dictated by the provided energy / Hamiltonian), so it is a very fast interaction. Due to the fact that it is a simulation, we have access to the underlying probability distribution immediately, for a QPU execution, the experiment would need to be reiterated a certain number of times to get similar results. Current computational frequencies are in-between 0.2 and 1 Hz depending on the scale of the problem, meaning 1 to 5 iterations per 5 second window.

Cloud emulation

Pulser Studio is also integrated into the Cloud platform, allowing it to use our GPU-based emulators to run sequences on large-scale registers. The number of qubits you can simulate with the Cloud emulation is not limited.

Note

Pulser Studio is accessible to anyone, but only people having access to the Pasqal Cloud platform will have access to its cloud-related features.

The cloud emulation tab.

From the Cloud emulation tab, you choose:

• a cloud platform Project you are associated to ;
• the backend (aka. the emulator) you want to execute your simulation on ;
• the number of runs of your sequence, i.e. the number of times it will be repeated, in order to tend to the most accurate probability distribution.

After clicking on the Send to emulator button, a “batch” object is created on the cloud platform, representing the multiple executions of your sequence on the selected emulator. This batch is assigned a unique ID. By clicking it, you will be directed to the User portal when you can monitor the batch status and see its results.

Example of an emulation sent as a batch to the cloud platform.

Important

Contrary to the local emulation, the results of a cloud-based emulation are not visible in Pulser Studio itself and require going to the cloud User portal to be visualized.