## QPU Specifications

## Technical Publications

## Rigetti 8Q Agave

#### ONLINE

Date Deployed: June 4, 2018

Rigetti 8Q-Agave is a superconducting quantum processor consisting

of 8 physical qubits arranged in a ring topology.

**Rigetti 8Q topology**. Schematic of Rigetti 8Q showing the fixed-frequency qubits (gold circles) and the frequency-tunable qubits (teal circles).

8Q-Agave uses asymmetric transmon qubits that are frequency tunable via an applied magnetic flux. We use this tunability to enable multi-qubit gates* *through parametrically modulated interactions*. *Compact lumped-element resonators allow for individual

readout of each qubit in the ring.

## Performance Parameters

All of the parameters listed in this table have been measured at cryogenic

temperatures. The errors indicate the standard deviation of the averaged value.

Note that these values tend to drift in time.

The single-qubit gate fidelities listed in Table 1 are extracted from randomized

benchmarking protocols. The reported gate fidelity is related to the randomized

benchmarking (RB) decay constant p in the following way:

The readout fidelities listed in Table 1 are so-called “assignment fidelities”. That is,

they correspond to the probability of correctly identifying 0 and 1 from an ensemble of

states prepared in the computational basis states.

Two-qubit entangling gates are characterized using quantum process tomography (QPT).

In estimating gate fidelities using QPT, we compensated for the known readout infidelities

and applied complete positivity (CP) constraints to the recovered process matrix.

## Rigetti 19Q-Acorn

#### OFFLINE

Date Deployed: December 17, 2017

Rigetti 19Q-Acorn is a multi-qubit quantum device with higher-connectivity. It comprises 20 physical qubits with capacitive couplings.

As with 8Q-Agave, an alternating arrangement of fixed-frequency and tunable-frequency qubits enables 2-qubit gates between adjacent qubits. To maintain a high degree of isolation and control, Rigetti employs superconducting thru-silicon vias in the chip design.

## Performance Specs

All of the parameters listed in this table have been measured at cryogenic temperatures. The errors indicate the standard deviation of the averaged value. Note that these values tend to drift in time.

The single-qubit gate fidelities listed in Table 1 are extracted from randomized benchmarking protocols. The reported gate fidelity is related to the randomized benchmarking (RB) decay constant p in the following way:

The readout fidelities listed in Table 1 are so-called “assignment fidelities”. That is, they correspond to the probability of correctly identifying 0 and 1 from an ensemble of states prepared in the computational basis states.

Two-qubit entangling gates are characterized using quantum process tomography (QPT). In estimating gate fidelities using QPT, we compensated for the known readout infidelities and applied complete positivity (CP) constraints to the recovered process matrix.