The Bubble Bit Technique as Improvement of HDL-Based Quantum Circuits Simulation

When performed on a classical computer, the simulation of quantum circuits is usually an exponential job. The methodology based on Hardware Description Languages is able to isolate the entanglement as source of simulation complexity. However, it was shown that this methodology is not efficient in the presence of total entanglement, and the probability of such a situation grows exponentially with the number of qubits [11]. The bubble bit technique is designed to avoid the entangled representation of the quantum state, thus allowing the HDL structural description of the quantum circuit, which requires polynomial resources for simulation. We provide experimental runtimes, obtained by simulation of quantum arithmetic and Groverýs algorithm circuits, which indicate substantial runtime speedup.