  Classical simulation of quantum computation is vital for verifying quantum
devices and assessing quantum algorithms. We present a new quantum circuit
simulator developed on the Sunway TaihuLight supercomputer. Compared with other
simulators, the present one is distinguished in two aspects. First, our
simulator is more versatile. The simulator consists of three mutually
independent parts to compute the full, partial and single amplitudes of a
quantum state with different methods. It has the function of emulating the
effect of noise and support more kinds of quantum operations. Second, our
simulator is of high efficiency. The simulator is designed in a two-level
parallel structure to be implemented efficiently on the distributed many-core
Sunway TaihuLight supercomputer. Random quantum circuits can be simulated with
40, 75 and 200 qubits on the full, partial and single amplitude, respectively.
As illustrative applications of the simulator, we present a quantum fast
Poisson solver and an algorithm for quantum arithmetic of evaluating
transcendental functions. Our simulator is expected to have broader
applications in developing quantum algorithms in various fields.
