论文标题
使用电路优化快速模拟量子算法
Fast simulation of quantum algorithms using circuit optimization
论文作者
论文摘要
经典模拟器在量子算法的开发和基准中起主要作用,并且实际上任何用于量子计算的软件框架提供了运行模拟器上算法的选项。但是,量子模拟器的开发与其他软件框架基本上分开,相反,该框架着眼于可用性和编译。在这里,我们通过提出专门的编译器通行证来减少任意电路的模拟时间来证明共同开发和集成模拟器和编译器的优势。尽管该概念广泛适用,但我们提出了基于Intel Quantum Simulator(高性能分布式模拟器)的具体实现。作为这项工作的一部分,我们通过与量子状态的表示相关的其他功能扩展了其实施。通过更改在分布式内存中存储状态幅度的顺序,可以减少通信开销,这一概念类似于分布式Schroedinger-Schroedinger-type模拟器之间的局部和全局码头之间的区别。然后,我们通过引入有关数据移动的特殊指令作为量子电路的一部分来实施编译器通行证来利用新功能。这些说明针对模拟器的独特功能,并且在实际量子设备中没有类似物。为了量化优势,我们比较有或没有优化的情况下模拟随机电路所需的时间。模拟时间通常减半。
Classical simulators play a major role in the development and benchmark of quantum algorithms and practically any software framework for quantum computation provides the option of running the algorithms on simulators. However, the development of quantum simulators was substantially separated from the rest of the software frameworks which, instead, focus on usability and compilation. Here, we demonstrate the advantage of co-developing and integrating simulators and compilers by proposing a specialized compiler pass to reduce the simulation time for arbitrary circuits. While the concept is broadly applicable, we present a concrete implementation based on the Intel Quantum Simulator, a high-performance distributed simulator. As part of this work, we extend its implementation with additional functionalities related to the representation of quantum states. The communication overhead is reduced by changing the order in which state amplitudes are stored in the distributed memory, a concept analogous to the distinction between local and global qubits for distributed Schroedinger-type simulators. We then implement a compiler pass to exploit the novel functionalities by introducing special instructions governing data movement as part of the quantum circuit. Those instructions target unique capabilities of simulators and have no analogue in actual quantum devices. To quantify the advantage, we compare the time required to simulate random circuits with and without our optimization. The simulation time is typically halved.