# Optimized Compilation of Aggregated Instructions for Realistic Quantum   Computers

**Authors:** Yunong Shi, Nelson Leung, Pranav Gokhale, Zane Rossi, David I., Schuster, Henry Hoffman, Fred T. Chong

arXiv: 1902.01474 · 2019-02-19

## TL;DR

This paper introduces a novel quantum compilation method that aggregates and optimizes multiple logical operations into larger units, significantly reducing latency and improving the efficiency of quantum programs on real hardware.

## Contribution

It proposes a universal quantum compilation approach that aggregates multiple operations and optimizes control pulses, bridging the gap between logical instructions and physical implementation.

## Key findings

- Achieves an average 5x speedup in quantum program execution
- Maximum speedup of 10x demonstrated on simulations
- Enhances the feasibility of near-term quantum applications

## Abstract

Recent developments in engineering and algorithms have made real-world applications in quantum computing possible in the near future. Existing quantum programming languages and compilers use a quantum assembly language composed of 1- and 2-qubit (quantum bit) gates. Quantum compiler frameworks translate this quantum assembly to electric signals (called control pulses) that implement the specified computation on specific physical devices. However, there is a mismatch between the operations defined by the 1- and 2-qubit logical ISA and their underlying physical implementation, so the current practice of directly translating logical instructions into control pulses results in inefficient, high-latency programs. To address this inefficiency, we propose a universal quantum compilation methodology that aggregates multiple logical operations into larger units that manipulate up to 10 qubits at a time. Our methodology then optimizes these aggregates by (1) finding commutative intermediate operations that result in more efficient schedules and (2) creating custom control pulses optimized for the aggregate (instead of individual 1- and 2-qubit operations). Compared to the standard gate-based compilation, the proposed approach realizes a deeper vertical integration of high-level quantum software and low-level, physical quantum hardware. We evaluate our approach on important near-term quantum applications on simulations of superconducting quantum architectures. Our proposed approach provides a mean speedup of $5\times$, with a maximum of $10\times$. Because latency directly affects the feasibility of quantum computation, our results not only improve performance but also have the potential to enable quantum computation sooner than otherwise possible.

## Figures

21 figures with captions in the complete paper: https://tomesphere.com/paper/1902.01474/full.md

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Source: https://tomesphere.com/paper/1902.01474