IonQ provider

Tip

First-time users automatically get free $500 (USD) Azure Quantum Credits for use with each participating quantum hardware provider. If you have consumed all the credits and you need more, you can apply to the Azure Quantum Credits program.

IonQ’s quantum computers perform calculations by manipulating the hyperfine energy states of Ytterbium ions with lasers. Atoms are nature's qubits — every qubit is identical within and between programs. Logical operations can also be performed on any arbitrary pair of qubits, enabling complex quantum programs unhindered by physical connectivity. Want to learn more? Read IonQ’s trapped ion quantum computer technology overview.

• Publisher: IonQ
• Provider ID: ionq

The following targets are available from this provider:

Target name	Target ID	Number of qubits	Description
Quantum simulator	ionq.simulator	29 qubits	IonQ's cloud-based idealized simulator. Free of cost.
IonQ Harmony	ionq.qpu	11 qubits	IonQ's trapped-ion quantum computer.
IonQ Aria	ionq.qpu.aria-1	23 qubits	IonQ's Aria trapped-ion quantum computer.

IonQ's targets correspond to a No Control Flow profile. For more information about this target profile and its limitations, see Understanding target profile types in Azure Quantum.

Quantum simulator

GPU-accelerated idealized simulator supporting up to 29 qubits, using the same set of gates IonQ provide on its quantum hardware—a great place to preflight jobs before running them on an actual quantum computer.

• Job type: Simulation
• Data Format: ionq.circuit.v1
• Target ID: ionq.simulator
• Target Execution Profile: No Control Flow

IonQ Harmony quantum computer

The IonQ Harmony is a trapped ion quantum computer and is dynamically reconfigurable in software to use up to 11 qubits. All qubits are fully connected, meaning you can run a two-qubit gate between any pair.

• Job type: Quantum Program
• Data Format: ionq.circuit.v1
• Target ID: ionq.qpu
• Target Execution Profile: No Control Flow

Parameter Name	Type	Required	Description
shots	int	No	Number of experimental shots. Defaults to 500.

System timing

Measure	Average time duration (µs)
T1	>10^7
T2	200,000
Single-qubit gate	10
Two-qubit gate	210
Readout	100
Register reset	25
Coherence time / gate duration	1667

System fidelity

Operation	Average fidelity
Single-qubit gate	99.35% (SPAM corrected)
Two-qubit gate	96.02% (not SPAM corrected)
SPAM*	99.3 - 99.8%
Geometric mean op	98.34%

* State Preparation and Measurement (SPAM): This measurement determines how accurately a quantum computer can set a qubit into its initial state and then measure the result at the end.

IonQ Aria quantum computer

IonQ Aria is IonQ's latest generation of trapped-ion quantum computer. With a 23-qubit dynamically reconfigurable sytem, IonQ Aria is available exclusively on Azure Quantum. For more information, see IonQ Aria (ionq.com) .

• Job type: Quantum Program
• Data Format: ionq.circuit.v1
• Target ID: ionq.qpu.aria-1
• Target Execution Profile: No Control Flow

Parameter Name	Type	Required	Description
shots	int	No	Number of experimental shots.

System timing

Measure	Average time duration
T1	10-100 s
T2	1 s
Single-qubit gate	135 µs
Two-qubit gate	600 µs

System fidelity

Operation	Average fidelity
Single-qubit gate	99.95% (SPAM corrected)
Two-qubit gate	99.6% (not SPAM corrected)
SPAM*	99.61%

* State Preparation and Measurement (SPAM): This measurement determines how accurately a quantum computer can set a qubit into its initial state and then measure the result at the end.

IonQ Aria is available through Azure Quantum Credits plan and a separate billing plan. For more information, see Azure Quantum pricing.

Native gates support and usage

By default IonQ allows you to specify a quantum circuit using an abstract set of quantum gates, called qis, which allows flexibility and portability when writing an algorithm without worrying about optimization for the hardware.

However, in some advanced usage cases, you might want to define a circuit directly on native gates in order to be closer to the hardware and bypass optimization. The native gate set is the set of quantum gates that are physically executed in the quantum processor, and they map the circuit to those as part of the execution.

For more information, see Getting Started With Native Gates (ionq.com).

In order to use the native gate set when submitting Qiskit jobs to Azure Quantum, you specify the gateset parameter when initializing the backend as in the example below:

# Here 'provider' is an instance of AzureQuantumProvider
backend = provider.get_backend("ionq.qpu", gateset="native")

Parameter Name	Type	Required	Description
gateset	string	No	Specifies the set of gates that will be used to define a circuit. A value of qis corresponds to the abstract gates (default behavior) and native to the IonQ hardware native gates.

For more information about Qiskit jobs, see Submit a circuit with Qiskit using an Azure Quantum notebook.

Input format

In Q#, the output of a quantum measurement is a value of type Result, which can only take the values Zero and One. When you define a Q# operation, it can only be submitted to IonQ hardware if the return type is a collection of Results, that is, if the output of the operation is the result of a quantum measurement. The reason for this is because IonQ builds a histogram from the returned values, so it restricts the return type to Results to simplify creating this histogram.

IonQ's targets correspond to the No Control Flow profile. This profile can't run quantum operations that require the use of the results from qubit measurements to control the program flow.

Note

Currently, you can't submit quantum programs that apply operations on qubits that have been measured in No Control Flow targets, even if you don't use the results to control the program flow. That is, No Control Flow targets don't allow mid-circuit measurements.

For example, the following code can not be run on a No Control Flow target:

operation MeasureQubit(q : Qubit) : Result { 
   return M(q); 
}

operation SampleMeasuredQubit(q : Qubit) : Result {
    H(MeasureQubit(q));
    return M(MeasureQubit(q));
}

Output format

When you submit a quantum program to the IonQ simulator, it returns the histogram created by the measurements. The IonQ simulator doesn't sample the probability distribution created by a quantum program but instead returns the distribution scaled to the number of shots. This is most apparent when you submit a single shot circuit. You will see multiple measurement results in the histogram for one shot. This behavior is inherent to IonQ simulator, while IonQ QPU actually runs the program and aggregates the results.

Pricing

To see IonQ billing plan, visit Azure Quantum pricing.

Limits & Quotas

IonQ quotas are tracked based on the QPU usage unit, which is qubit-gate-shot (QGS). The resource usage is credited against your account.

Every quantum program consists of $N$ quantum logical gates of one or more qubits, and is executed for a certain number of shots. The number of gate-shots is calculated by the following formula:

$$ QGS = N · C $$

where:

• $N$ is the number of one- or two-qubit gates submitted
• $C$ is the number of execution shots requested

Quotas are based on plan selection and can be increased with a support ticket. To see your current limits and quotas, go to the Credits and quotas blade and select the Quotas tab of your workspace on the Azure portal. For more information, see Azure Quantum quotas.

Note

If you are using an Azure Quantum Credits plan, and not a billing plan, the quotas information maps to your allocated credits. In that case, the quota lists the total number of credits you have received.

IonQ best practices and connectivity graph

To see recommended best practices for the IonQ QPU, see IonQ Best Practices (ionq.com).