The Fraunhofer quantum computing simulator
Fraunhofer FIRST develops a computing service and collaborative workspace providing a convenient tool for simulation and investigation of quantum algorithms1. To broaden the twenty qubit limit of workstation-based simulations to the next qubit decade we provide a dedicated high memorized Linux cluster with fast Myrinet interconnection network together with a adapted parallel simulator engine. This simulation service supplemented by a collaborative workspace is usable everywhere via web interface and integrates both hardware and software as collaboration and investigation platform for the quantum community. The modular design of our simulator engine enables the application of various implementations and simulation techniques and is open for extensions motivated by the experience of the users. The beta test version realizes all common one, two and three qubit gates, arbitrary one and two bit gates, orthogonal measurements as well as special gates like Oracle, Modulo funct ion and Quantum Fourier Transformation. The main focus of our project is the simulation of experimentally realizations of quantum algorithms which will make it feasible to understand the differences between real and ideal quantum devices and open the view for new algorithms and applications. That is why the simulator also can work with arbitrary Hamiltonians yielding its unitary transformation, spectrum and eigenvectors. To realize the various simulation tasks we integrate various implementations. The test version is able to simulate small quantum circuits and Hamiltonians exactly, the latter through the use of a standard diagonalization procedure. Circuits up to thirty qubits can be simulated exactly as well; Hamiltonians of that size, however, have to be approximated according to the Trotter formulae. For a restricted gate set we also develop a tensor-sum implementation, which makes it feasible to investigate circuits with up to sixty qubits.