What’s new

The most recent updates and features in IBM Quantum Experience

January 2021

  • Premium systems now support mid-circuit measurement and qubit re-use!

    Mid-circuit measurement (requires Qiskit Terra 0.16.1 or later) makes it possible to measure an individual qubit at any point in the circuit, not just at the end. You can also measure qubits multiple times within a circuit. Measurements can be triggered independently.

    In conjunction with Conditional Reset on IBM Quantum Systems, you can now re-use qubits.

    This opens up the opportunity for a wider variety of experiments, such as

    • heralding

    • monitoring qubit evolution

    • multiple measurement of ancilla qubits for post selection

    For more information, see the Mid-Circuit Measurements Tutorial.

December 2020

  • New set of basis gates on our open systems.

    The set of basis gates for IBM Quantum open systems has changed from {u1, u2, u3, cx} to {id, rz, sx, x, cx}. This new basis set will bring us closer to the level of control necessary to get a Quantum Volume of 64 (this requires Qiskit 0.22 or greater).

  • Visualizations in Circuit Composer now reflect probabilistic instructions.

    Add an operation such as a measurement, conditional gate, or a reset to a circuit on the Composer, and the visualizations below the editor will reflect these probabilistic instructions.

    Randomness in the visualizations is based on a seed number, which corresponds to a single instance of the statevector simulator. Now you can see the seed number above the Composer — you can also change that number to set a new seed, and observe any differences in the visualizations of your circuit.

  • New widgets in Quantum Lab!

    The new Circuit Composer widget in Lab requires no installation. Interact with the Composer from within the Jupyter notebook environment, alongside Qiskit code. Visit Using the Circuit Composer and Visualizer widgets to learn more.

  • Conditional reset is now on all capable systems!

    All systems except ibmq_armonk and ibmq_melbourne are now enabled with conditional reset.

    Visit these tutorials to learn more.

    Conditional Reset on IBM Quantum Systems

    Selectable Discriminators

November 2020

  • Check out the updates to the operations list, including the new control modifier!

    Drag the control modifier to a gate to add a control to it, or use the contextual (right-click) menu to add or remove controls.

    control modifier.
  • Building circuits just got faster and easier!

    We’ve added standard controls such as multi-select, copy, and paste. You can also group multiple gates to create a custom unitary operation that functions as a single gate.

    Right-click menu options.

October 2020

  • Conditional reset is now available on some backends!

    Conditional reset is critical for allowing faster circuit execution by reducing the initialization time between shots, and allowing qubit reuse for circuits requiring a source of “fresh ancillas”.

    Visit these tutorials to learn more.

    Conditional Reset on IBM Quantum Systems

    Selectable Discriminators

September 2020

  • New public API page: Use this page to learn how to use the public REST APIs by reviewing the spec, exploring each API in detail, and working through an example.

  • See each qubit’s state, at a glance. The phase disk visualization, at the end of each qubit in your circuit, indicates the probability that the qubit is in the |1\rangle state, the phase of the state vector in the complex plane, and the reduced purity of the qubit state.

  • See the Quantum Volume of each backend: In the Your backends panel on the dashboard, the highest Quantum Volume (QV) recorded for each backend is now listed next to each backend’s name.

August 2020

Circuit Composer has a new look!

  • Workspace customization. Now you can see more information in a shared context. Use the View menu to choose which tools you see, then drag to resize, or click the menu in each window to further customize it. You can also choose a light or dark workspace theme.

  • Get to work faster. Navigating to Circuit Composer in the menu now takes you directly to your workspace. Click the file icon next to the Circuit name to see all of your previously saved circuits.

  • New operations added. A new color scheme groups operations by type. For details about the available gates and operations, see the Operations glossary.

    Note that the X gate is now represented by the symbol Target icon representing X gate. to match the other classical gates.

  • View Python code. Switch between editable OpenQASM and read-only Python code in the Code panel. Click the Open in Quantum Lab button to open the code in a Jupyter Notebook environment.

  • New q-sphere visualization. Unlike its cousin the Bloch sphere, the q-sphere uses nodes of varying sizes and colors arranged on a sphere to represent the state of a system of qubits. Click and drag the q-sphere to move it around! You can also view up to three visualizations at once. Note: we have removed the density matrix visualization.

  • PDF download. In addition to PNG and SVG, you can now download images of visualizations and circuits as PDFs.

  • No more built-in tabs. We have removed tabs from the interface. When you open a circuit from your list of circuit files, it will open in a new tab in your browser.

  • Easily run and monitor jobs. If you are signed in, you can click the Run Settings button to view and change Run settings, then use the Jobs panel to view your jobs, all without leaving the page. You can also see the qubit count of the backend, and a status tag if the backend is offline, not available, or in maintenance mode.

Qiskit Notebooks has a new name! Find Qiskit in the cloud under Quantum Lab.