How representative are Pauli errors of the complete set of errors that can occur on a quantum computer?

[quantumadmin]

Pauli errors, which are errors that arise from the application of Pauli operators (X, Y, Z) to qubits, are a subset of the complete set of errors that can occur on a quantum computer. While Pauli errors capture some important aspects of noise and imperfections in quantum hardware, they do not represent the full range of errors that quantum systems can experience.

In quantum computing, errors can result from various sources, including decoherence (loss of quantum coherence), relaxation (thermalization of qubits), environmental noise, control errors, and more. These errors can manifest in different ways, leading to a diverse range of effects on qubits and quantum gates.

Pauli errors are particularly relevant because they correspond to basic single-qubit and two-qubit errors that are often used as a building block for understanding and characterizing quantum noise. They provide a simple framework for error analysis and correction. However, they do not capture all possible error mechanisms and their correlations, especially more complex errors that can emerge in multi-qubit systems.

To get a comprehensive understanding of the error landscape on a quantum computer, it's important to consider more general forms of errors beyond the Pauli error model. This might involve characterizing and modeling higher-order errors, coherent errors, correlated errors, leakage errors, and any specific noise sources that are unique to the hardware technology being used.

Researchers and engineers working on quantum computing typically use a combination of theoretical analysis, numerical simulations, and experimental measurements to characterize and mitigate errors. This includes techniques like quantum error correction, fault tolerance, and error mitigation strategies that go beyond the Pauli error model to address the full range of errors that can impact quantum computations.