---
title: circuit (latest version)
description: API reference for qiskit_bosons.circuit in the latest version of qiskit-bosons
source: https://quantum.cloud.ibm.com/docs/en/api/qiskit-bosons/circuit
---

# Circuit Representation

With this module you can build [`QuantumCircuit`](/docs/api/qiskit/qiskit.circuit.QuantumCircuit) objects that are interpreted as acting on bosonic modes rather than qubits.

The following objects are simple type aliases to make this re-interpretation more clear:

|                                                                                                                                                              |                                                                                |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------ |
| [`BosonicDAGCircuit`](/docs/api/qiskit-bosons/circuit-bosonic-dag-circuit#qiskit_bosons.circuit.BosonicDAGCircuit "qiskit_bosons.circuit.BosonicDAGCircuit") | A type alias of [`DAGCircuit`](/docs/api/qiskit/qiskit.dagcircuit.DAGCircuit). |
| [`BosonicMode`](/docs/api/qiskit-bosons/circuit-bosonic-mode#qiskit_bosons.circuit.BosonicMode "qiskit_bosons.circuit.BosonicMode")                          | A type alias of [`Qubit`](/docs/api/qiskit/circuit#qiskit.circuit.Qubit).      |
| [`BosonicRegister`](/docs/api/qiskit-bosons/circuit-bosonic-register#qiskit_bosons.circuit.BosonicRegister "qiskit_bosons.circuit.BosonicRegister")          | A type alias of `QubitRegister`.                                               |
| [`BosonicSpecifier`](/docs/api/qiskit-bosons/circuit-bosonic-specifier#qiskit_bosons.circuit.BosonicSpecifier "qiskit_bosons.circuit.BosonicSpecifier")      | A type alias equivalent to Qiskit's `QubitSpecifier` but for bosonic modes.    |

For actually expressing your circuits, you should use the [`BosonicCircuit`](/docs/api/qiskit-bosons/circuit-bosonic-circuit#qiskit_bosons.circuit.BosonicCircuit "qiskit_bosons.circuit.BosonicCircuit") class along with the [`library`](/docs/api/qiskit-bosons/circuit-library#module-qiskit_bosons.circuit.library "qiskit_bosons.circuit.library") of [`BosonicGate`](/docs/api/qiskit-bosons/circuit-bosonic-gate#qiskit_bosons.circuit.BosonicGate "qiskit_bosons.circuit.BosonicGate") implementations.

|                                                                                                                                                                          |                                                                                                                      |
| ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | -------------------------------------------------------------------------------------------------------------------- |
| [`BosonicCircuit`](/docs/api/qiskit-bosons/circuit-bosonic-circuit#qiskit_bosons.circuit.BosonicCircuit "qiskit_bosons.circuit.BosonicCircuit")(num\_modes)              | A wrapper around [`QuantumCircuit`](/docs/api/qiskit/qiskit.circuit.QuantumCircuit) for expressing bosonic circuits. |
| [`BosonicGate`](/docs/api/qiskit-bosons/circuit-bosonic-gate#qiskit_bosons.circuit.BosonicGate "qiskit_bosons.circuit.BosonicGate")(name, num\_modes, /\[, params, ...]) | The base class for all bosonic gates.                                                                                |