Simulation of three-spin evolution under XX Hamiltonian on quantum processor of IBM-Quantum Experience

We simulate the evolution of three-node spin chain on the quantum processor of IBM Quantum Experience using the diagonalization of XX -Hamiltonian and representing the evolution operator in terms of CNOT operations and one-qubit rotations. We study the single excitation transfer from the first to the third node and show the significant difference between calculated and theoretical values of state transfer probability. Then, we propose a method reducing this difference by applying the two-parameter transformation including the shift and scale of the calculated probabilities. We demonstrate the universality of this transformation inside of the class of three-node evolutionary systems governed by the XX -Hamiltonian.