Mitigating Depolarizing Noise on Quantum Computers with Noise-Estimation Circuits

Abstract

A significant problem for current quantum computers is noise. While there are many distinct noise channels, the depolarizing noise model often appropriately describes average noise for large circuits involving many qubits and gates. We present a method to mitigate the depolarizing noise by first estimating its rate with a noise-estimation circuit and then correcting the output of the target circuit using the estimated rate. The method is experimentally validated on the simulation of the Heisenberg model. We find that our approach in combination with readout-error correction, randomized compiling, and zero-noise extrapolation produces results close to exact results even for circuits containing hundreds of CN OT gates.

Scalable error mitigation for noisy quantum circuits produces competitive expectation values

“…The study of quantum quenches with interacting spin-1/2 systems provides a rich playground for explorations of fundamental questions in condensed matter and statistical physics [34], and have already been explored extensively on analog quantum simulators [35][36][37]. These models are also becoming a particularly attractive application of existing, noisy, digital quantum computers [38][39][40][41] with their increased control and addressability. The spins can be naturally encoded in the physical qubits, nearest-neighbor interactions are accessible with the local-connectivity of the qubits, and relevant quantities can be measured by local, low-weight observables.…”

Measuring NISQ Gate-Based Qubit Stability Using a 1+1 Field Theory and Cycle Benchmarking

“…IBM has also recently introduced the IBM Qiskit Runtime Program to help streamline computations and minimize intra-day drift. In addition, other groups are investigating additional methods for improving the reliability of quantum processing computations [66,67,68,69,70] and comparisons among methods would be desirable.…”

Simulating open quantum many-body systems using optimised circuits in digital quantum simulation

“…The quantum device follows the qualitative behaviour, but fails to predict the power law behaviour. qubits and gates [43,55]. Second, we assume that the connectivity issue is resolved.…”

“…To characterise the impact of the noise, we explore the noise model on the IBM Quantum devices. In particular, we focus on the single-and two-qubit gate errors modelled by the depolarising channel which describes average noise in real devices for a large circuit [43,44]. We demonstrate that the data of our noise model describe those of the IBM Quantum device with high fidelity.…”