Point-and-click workflow tutorial

This is a step by step tutorial to demonstrate basic workflow with KQCircuits in KLayout Editor. It is assumed that KLayout and KQCircuits are already installed.

Do not assume all of the GUI makes sense. At the moment KLayout is version 0.27! It is already quite powerful, but most features make sense only after you know the API.

  1. Generate Demo chip

    1. Run KLayout Editor. On Windows you should have separate shortcuts for KLayout Viewer and KLayout Editor. On Linux you may have to go to File -> Setup -> Application -> Editing Mode and set Use editing mode by default to true, and restart KLayout. On macOS click on KLayout and on the top right corner click Preferences -> Application -> Editing Mode -> Use editing mode by default. Then restart the KLayout program.

    2. In the Libraries panel on the bottom left, choose Chip Library and drag and drop the Demo chip from there to the layout.

    3. Click Ok in the PCell parameters window that opens.

  2. For drag and drop changes, convert the top cell to static.

    1. Locate Cells panel on the left.

    2. Left click on the cell named ChipLibrary.Demo to select it.

    3. In the top menu, navigate to Edit->Cell->Convert to Static Cell. This converts a library cell into a locally defined cell and enables you to edit it.

    4. In the Cells panel, right click on the cell named Demo$1.

    5. From the drop down menu, select Show as new top.

  3. Change the shape of a waveguide.

    1. In the Layout panel locate a charge line of the qubit. It connects the top left launcher and the qubit.

    2. Click once on the charge line to select it.

    3. Press Shift+F2 to zoom in.

    4. From the Tools panel above the Layout panel select a tool Partial.

    5. Double click on the center of the charge line. A new node should appear there.

    6. Drag the new node with the mouse. The waveguide should change shape.

  4. Change a location of a qubit.

    1. Press F2 to see the whole top cell.

    2. Locate the qubit in the top left part of the chip.

    3. Drag a selection box around the qubit.

    4. From the Tools panel select Move.

    5. Click on the selection box.

    6. Click on a new location for a qubit.

  5. Disable a coupling port for the qubit.

    1. From the Tools panel select Select.

    2. Drag a selection box around the qubit.

    3. Click Shift+F2

    4. Press q.

    5. In the new Instance Properties window locate a tab PCell parameters.

    6. Scroll down in the list of parameters to locate Coupler lengths.

    7. Change the value in the text box to 100,160,0.

    8. Click Ok.

  6. Create a new qubit.

    1. Press F2 to see the whole top cell.

    2. From the toolbar select Instance.

    3. In the new Editor Options window locate Library.

    4. Using the drop-down menu select Qubit Library.

    5. Click on a button 🔍 a little bit to the left from the Library for older versions click ... a little bit to the left from the. Library.

    6. From the new Select Cell window select Swissmon and press Ok.

    7. In the Object Edit or Options window press Ok.

    8. Click at the location of the new qubits.

    9. Click Esc to finish placing qubits.

  7. Add the ground grid.

    1. In the top menu, navigate to KQCircuits -> Fill with ground plane grid. It may take some time to generate. Unhide ground grid in layers list located in the top right.