Single Transmon - Floating with charge lines#

We’ll be creating a 2D design and adding a single transmon qcomponent with charge lines.

Create a standard pocket transmon qubit with charge lines for a ground plane, with two pads connected by a junction.

[1]:
# So, let us dive right in. For convenience, let's begin by enabling
# automatic reloading of modules when they change.
%load_ext autoreload
%autoreload 2
[2]:
import qiskit_metal as metal
from qiskit_metal import designs, draw
from qiskit_metal import MetalGUI, Dict, open_docs
[3]:
# Each time you create a new quantum circuit design,
# you start by instantiating a QDesign class.

# The design class `DesignPlanar` is best for 2D circuit designs.

design = designs.DesignPlanar()
[4]:
#Launch Qiskit Metal GUI to interactively view, edit, and simulate QDesign: Metal GUI
gui = MetalGUI(design)
[5]:
# To force overwrite a QComponent with an existing name.
# This is useful when re-running cells in a notebook.
design.overwrite_enabled = True

A transmon qubit#

You can create a ready-made transmon qubit with charge lines from the QComponent Library, qiskit_metal.qlibrary.qubits. transmon_pocket_cl.py is the file containing our qubit so transmon_pocket_cl is the module we import. The TransmonPocketCL class is our transmon qubit. Like all quantum components, TransmonPocketCL inherits from QComponent.

Connector lines can be added using the connection_pads dictionary. Each connector pad has a name and a list of default properties.

[6]:
from qiskit_metal.qlibrary.qubits.transmon_pocket_cl import TransmonPocketCL

# Be aware of the default_options that can be overridden by user.
TransmonPocketCL.get_template_options(design)
[6]:
{'pos_x': '0um',
 'pos_y': '0um',
 'connection_pads': {},
 '_default_connection_pads': {'pad_gap': '15um',
  'pad_width': '125um',
  'pad_height': '30um',
  'pad_cpw_shift': '5um',
  'pad_cpw_extent': '25um',
  'cpw_width': 'cpw_width',
  'cpw_gap': 'cpw_gap',
  'cpw_extend': '100um',
  'pocket_extent': '5um',
  'pocket_rise': '65um',
  'loc_W': '+1',
  'loc_H': '+1'},
 'chip': 'main',
 'pad_gap': '30um',
 'inductor_width': '20um',
 'pad_width': '455um',
 'pad_height': '90um',
 'pocket_width': '650um',
 'pocket_height': '650um',
 'orientation': '0',
 'make_CL': True,
 'cl_gap': '6um',
 'cl_width': '10um',
 'cl_length': '20um',
 'cl_ground_gap': '6um',
 'cl_pocket_edge': '0',
 'cl_off_center': '50um',
 'hfss_wire_bonds': False,
 'q3d_wire_bonds': False,
 'hfss_inductance': '10nH',
 'hfss_capacitance': 0,
 'hfss_resistance': 0,
 'hfss_mesh_kw_jj': 7e-06,
 'q3d_inductance': '10nH',
 'q3d_capacitance': 0,
 'q3d_resistance': 0,
 'q3d_mesh_kw_jj': 7e-06,
 'gds_cell_name': 'my_other_junction'}
[7]:
transmon_options = dict(
    pos_x = '1mm',
    pos_y = '2mm',
    orientation = '90',

    connection_pads=dict(
        a = dict(loc_W=+1, loc_H=-1, pad_width='70um', cpw_extend = '50um'),
        b = dict(loc_W=-1, loc_H=-1, pad_width='125um', cpw_extend = '50um', pad_height='60um'),
        c = dict(loc_W=+1, loc_H=+1, pad_width='110um', cpw_extend = '50um')
    ),

    gds_cell_name='FakeJunction_01',
)

# Create a new Transmon Pocket object with name 'Q1'
q1 = TransmonPocketCL(design, 'Q1', options=transmon_options)

gui.rebuild()  # rebuild the design and plot
gui.autoscale() # resize GUI to see QComponent
gui.zoom_on_components(['Q1']) #Can also gui.zoom_on_components([q1.name])

Let’s see what the Q1 object looks like

[8]:
q1 #print Q1 information
[8]:
name:    Q1
class:   TransmonPocketCL      
options: 
  'pos_x'             : '1mm',
  'pos_y'             : '2mm',
  'connection_pads'   : {
       'a'                 : {
            'pad_gap'           : '15um',
            'pad_width'         : '70um',
            'pad_height'        : '30um',
            'pad_cpw_shift'     : '5um',
            'pad_cpw_extent'    : '25um',
            'cpw_width'         : 'cpw_width',
            'cpw_gap'           : 'cpw_gap',
            'cpw_extend'        : '50um',
            'pocket_extent'     : '5um',
            'pocket_rise'       : '65um',
            'loc_W'             : 1,
            'loc_H'             : -1,
                             },
       'b'                 : {
            'pad_gap'           : '15um',
            'pad_width'         : '125um',
            'pad_height'        : '60um',
            'pad_cpw_shift'     : '5um',
            'pad_cpw_extent'    : '25um',
            'cpw_width'         : 'cpw_width',
            'cpw_gap'           : 'cpw_gap',
            'cpw_extend'        : '50um',
            'pocket_extent'     : '5um',
            'pocket_rise'       : '65um',
            'loc_W'             : -1,
            'loc_H'             : -1,
                             },
       'c'                 : {
            'pad_gap'           : '15um',
            'pad_width'         : '110um',
            'pad_height'        : '30um',
            'pad_cpw_shift'     : '5um',
            'pad_cpw_extent'    : '25um',
            'cpw_width'         : 'cpw_width',
            'cpw_gap'           : 'cpw_gap',
            'cpw_extend'        : '50um',
            'pocket_extent'     : '5um',
            'pocket_rise'       : '65um',
            'loc_W'             : 1,
            'loc_H'             : 1,
                             },
                        },
  'chip'              : 'main',
  'pad_gap'           : '30um',
  'inductor_width'    : '20um',
  'pad_width'         : '455um',
  'pad_height'        : '90um',
  'pocket_width'      : '650um',
  'pocket_height'     : '650um',
  'orientation'       : '90',
  'make_CL'           : True,
  'cl_gap'            : '6um',
  'cl_width'          : '10um',
  'cl_length'         : '20um',
  'cl_ground_gap'     : '6um',
  'cl_pocket_edge'    : '0',
  'cl_off_center'     : '50um',
  'hfss_wire_bonds'   : False,
  'q3d_wire_bonds'    : False,
  'hfss_inductance'   : '10nH',
  'hfss_capacitance'  : 0,
  'hfss_resistance'   : 0,
  'hfss_mesh_kw_jj'   : 7e-06,
  'q3d_inductance'    : '10nH',
  'q3d_capacitance'   : 0,
  'q3d_resistance'    : 0,
  'q3d_mesh_kw_jj'    : 7e-06,
  'gds_cell_name'     : 'FakeJunction_01',
module:  qiskit_metal.qlibrary.qubits.transmon_pocket_cl
id:      1

Save screenshot as a .png formatted file.

[9]:
gui.screenshot()
../../_images/circuit-examples_A.Qubits_07-Transmon_floating_cl_12_0.png
[10]:
# Screenshot the canvas only as a .png formatted file.
gui.figure.savefig('shot.png')

from IPython.display import Image, display
_disp_ops = dict(width=500)
display(Image('shot.png', **_disp_ops))

../../_images/circuit-examples_A.Qubits_07-Transmon_floating_cl_13_0.png

Closing the Qiskit Metal GUI#

[11]:
gui.main_window.close()
[11]:
True
[ ]:

For more information, review the Introduction to Quantum Computing and Quantum Hardware lectures below

  • Superconducting Qubits I: Quantizing a Harmonic Oscillator, Josephson Junctions Part 1
Lecture Video Lecture Notes Lab
  • Superconducting Qubits I: Quantizing a Harmonic Oscillator, Josephson Junctions Part 2
Lecture Video Lecture Notes Lab
  • Superconducting Qubits I: Quantizing a Harmonic Oscillator, Josephson Junctions Part 3
Lecture Video Lecture Notes Lab
  • Superconducting Qubits II: Circuit Quantum Electrodynamics, Readout and Calibration Methods Part 1
Lecture Video Lecture Notes Lab
  • Superconducting Qubits II: Circuit Quantum Electrodynamics, Readout and Calibration Methods Part 2
Lecture Video Lecture Notes Lab
  • Superconducting Qubits II: Circuit Quantum Electrodynamics, Readout and Calibration Methods Part 3
Lecture Video Lecture Notes Lab