Основні поняття
Robust Amplitude Estimation (RAE) can significantly reduce the error in estimating the ground state energy of the hydrogen molecule compared to direct measurement techniques, despite the inherent limitations of current quantum hardware.
Анотація
The study explores the experimental implementation of Robust Amplitude Estimation (RAE) on IBM quantum devices to estimate the ground state energy of one- and two-qubit Hamiltonian systems representing the hydrogen molecule.
Key highlights:
- RAE has the potential to offer quadratic speedups over traditional methods in estimating expectation values, but its performance is affected by noise and device characteristics.
- Experiments on the ibmq_montreal device showed that RAE can achieve a significant reduction in sampling requirements compared to direct measurement techniques.
- For the two-qubit hydrogen molecule Hamiltonian, the RAE implementation demonstrated two orders of magnitude better accuracy compared to direct sampling and achieved chemical accuracy.
- The performance of RAE can be adversely impacted by coherent error and device stability, and does not always correlate with the average gate error.
- These results highlight the importance of adapting quantum computational methods to hardware specifics to realize their full potential in practical scenarios.
Статистика
The ground state energy of the hydrogen molecule in the STO-3G minimal basis can be represented by a one-qubit Hamiltonian with parameters a(1) = -0.329, b(1) = 0.181, c(1) = -0.788, and a two-qubit Hamiltonian with parameters a(2) = 0.2388, b(2) = 0.3466, c(2) = -0.4439, d(2) = 0.5736, e(2) = 0.09075, f(2) = 0.09075.
Цитати
"RAE can reduce the scaling of the number of state preparations needed to evaluate the VQE cost function with precision ϵ from O(1/ϵ^2) to O(1/ϵ^α), where α ∈[1, 2]."
"These findings reveal its potential to enhance computational efficiencies in quantum chemistry applications despite the inherent limitations posed by hardware noise."