Simplified Fermionic Scattering State Preparation for the NISQ Era

Abstract: With quantum computers steadily improving, large volume quantum scattering simulations is getting very close. Yet, in the noisy intermediate scale quantum (NISQ) era, we are limited to shallow circuits on the order of a thousand layers. Thus, accurate and efficient state preparation methods are needed. We introduce a simplified fermionic scattering state preparation method that reduces circuit depth significantly by partially relaxing the fermionic condition. Using the 1+1D transverse field Ising model as our test bed with exact diagonalization and time evolving block decimation with matrix product states, we show that our simplified states retain nearly all of the behavior of the true fermionic state while being prepared on just a handful of qubits. We also show promising early results on IonQ Forte 1.