Fig. 1: Circuit constructions.
From: Nearest centroid classification on a trapped ion quantum computer
a The data loader circuit for an 8-dimensional data point. The angles of the RBS(θ) gates starting from left to right and top to bottom correspond to (θ1, θ2, …, θ7). b The distance estimation circuit for two 8-dimensional data points. The circuit in time steps 0–3 corresponds to the parallel loader for the first data point and the circuit in time steps 4–6 corresponds to the inverse parallel loader circuit for the second data point (excluding the last X gate). The probability the first qubit is measured in state \(\left|1\right\rangle\) is exactly the square of the inner product of the two data points. c The optimized distance estimation circuit for two 8-dimensional data points. Each pair of RBS gates that are applied to the same consecutive qubits in time steps 3 and 4 in the circuit of b are combined to one gate whose parameter θ is equal to θ1 + θ2, where θ1 is the parameter of the first gate and θ2 is the parameter of the second gate.
