---
title: FermionicSpecifier (latest version)
description: API reference for qiskit_fermions.circuit.FermionicSpecifier in the latest version of qiskit-fermions
source: https://eu-de.quantum.cloud.ibm.com/docs/en/api/qiskit-fermions/circuit-fermionic-specifier
---

# FermionicSpecifier

Type: [`TypeAlias`](https://docs.python.org/3/library/typing.html#typing.TypeAlias)

Default value: `qiskit.circuit.Qubit | qiskit.circuit.QuantumRegister | int | slice | collections.abc.Sequence[qiskit.circuit.Qubit | int]`

A type alias equivalent to Qiskit’s `QubitSpecifier` but for fermionic modes.