arXiv subjects

Soheil Khadirsharbiyani

Publications and source records attributed to Soheil Khadirsharbiyani.

2 recordsLinked to original sources

arXiv2023

DC: Depth Control on Quantum Classical Circuit

The growing prevalence of near-term intermediate-scale quantum (NISQ) systems has brought forth a heightened focus on the issue of circuit reliability. Several quantum computing activities, such as circuit design and multi-qubit mapping, are focused on enhancing reliability via the use of different optimization techniques. The optimization of quantum classical circuits has been the subject of substantial research, with a focus on techniques such as ancilla-qubit reuse and tactics aimed at minimizing circuit size and depth. Nevertheless, the reliability of bigger and more complex circuits remains a difficulty due to potential failures or the need for time-consuming compilation processes, despite the use of modern optimization strategies. This study presents a revolutionary Depth Control (DC) methodology that involves slicing and lowering the depth of conventional circuits. This strategy aims to improve the reliability and decrease the mapping costs associated with quantum hardware. DC provides reliable outcomes for circuits of indefinite size on any Noisy Intermediate-Scale Quantum (NISQ) system. The experimental findings demonstrate that the use of DC leads to a substantial improvement in the Probability of Success Threshold (PST), with an average increase of 11x compared to non-DC baselines. Furthermore, DC exhibits a notable superiority over the next best outcome by ensuring accurate outputs with a considerable margin. In addition, the utilization of Design Compiler (DC) enables the execution of mapping and routing optimizations inside a polynomial-time complexity, which represents an advancement compared to previously suggested methods that need exponential time.

quant-ph↗

arXiv2022

Quantum Circuit Resizing

Existing quantum systems provide very limited physical qubit counts, trying to execute a quantum algorithm/circuit on them that have a higher number of logical qubits than physically available lead to a compile-time error. Given that it is unrealistic to expect existing quantum systems to provide, in near future, sufficient number of qubits that can accommodate large circuit, there is a pressing need to explore strategies that can somehow execute large circuits on small systems. In this paper, first, we perform an analysis to identify the qubits that are most suitable for circuit resizing. Our results reveal that, in most quantum programs, there exist qubits that can be reused mid-program to serially/sequentially execute the circuit employing fewer qubits. Motivated by this observation, we design, implement and evaluate a compiler-based approach that i) identifies the qubits that can be most beneficial for serial circuit execution; ii) selects those qubits to reuse at each step of execution for size minimization of the circuit; and iii) minimizes Middle Measurement (MM) delays due to impractical implementation of shots to improve the circuit reliability. Furthermore, since our approach intends to execute the circuits sequentially, the crosstalk errors can also be optimized as a result of the reduced number of concurrent gates. The experimental results indicate that our proposed approach can (i) execute large circuits that initially cannot fit into small circuits, on small quantum hardware, and (ii) can significantly improve the PST of the results by 2.1X when both original and our serialized programs can fit into the target quantum hardware.

cs.ET↗