Towards simulating time evolution of specific quantum many-body system by lower counts of quantum gates


 In the noisy intermediate-scale quantum (NISQ) era, quantum computers have become important tools to simulate the real-time evolution of strong correlated many-body systems. The general scheme of designing quantum circuits to simulate the quantum dynamics is based on the Trotter- Suzuki decomposition technique, which has its limitation because the accuracy of evolution process depends on the size of trotter steps when the evolution operator is decomposed as quantum gates. Going beyond the limitation of Trotter-Suzuki scheme, we design a parameterized quantum circuit named α-circuit with simple determined size and the only one control parameter θ to simulate the real-time evolution of the speci c XXX Heisenberg model with the speci c initial state │000 ●●● >. The α-circuit can accurately generate the time-evolution results by tuning parameter θ, which means the circuit can also be regarded as a good state preparation machine (SPM).