2007/12/19 by T. Schulte-Herbrueggen, Schulte-Herbrueggen, T., Andreas Spoerl +5 · 1 citation
Computer Science · Physics and Astronomy · #FOS: Physical sciences #Parallel Computing and Optimization Techniques #Quantum Computing Algorithms and Architecture #Quantum Physics (quant-ph) #Quantum-Dot Cellular Automata #quant-ph
paper · pdf · doi:10.48550/arxiv.0712.3227
substantially enlarged update with new sections; 19 pages, 17 figures; comments welcome
openalex publication_date 2007/12/19 · arxiv created 2008/12/22 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present a quantum CISC compiler and show how to assemble complex instruction sets in a scalable way. Enlarging the toolbox of universal gates by optimised complex multi-qubit instruction sets thus paves the way to fight decoherence for realistic settings. Compiling a quantum module into the machine code for steering a concrete quantum hardware device lends itself to be tackled by means of optimal quantum control. To this end, there are two opposite approaches: (i) one may use a decomposition into the restricted instruction set (RISC) of universal one- and two-qubit gates, which in turn have prefabricated translations into the machine code or (ii) one may prefer to generate the entire target module directly by a complex instruction set (CISC) of available controls. Here we advocate direct compilation up to the limit of system size a classical high-performance parallel computer cluster can reasonably handle. For going beyond these limits, i.e. for large systems we propose a combined way, namely (iii) to make recursive use of medium-sized building blocks generated by optimal control in the sense of a quantum CISC compiler. The advantage of the method over standard RISC compilations into one- and two-qubit universal gates is explored on the parallel cluster HLRB-II (with a total LINPACK performance of 63.3 TFlops/s) for the quantum Fourier transform, the indirect SWAP gate as well as for multiply-controlled CNOT gates. Implications for upper limits to time complexities are also derived.