Pauli Matrices
BackAction.sigma_x — ConstantPauli Matrix $\sigma_x = |0\rangle\langle 1| + |1\rangle\langle 0|$
BackAction.sigma_y — ConstantPauli Matrix $\sigma_y = i|0\rangle\langle 1| - i|1\rangle\langle 0|$
BackAction.sigma_z — ConstantPauli Matrix $\sigma_z = |0\rangle\langle 0| - |1\rangle\langle 1|$
BackAction.sigma_m — ConstantLowering operator $\sigma_- = |0\rangle\langle 1|$
BackAction.sigma_p — ConstantRaising operator $\sigma_+ = |1\rangle\langle 0|$
Runge-Kutta 4 Solver
To run the test against the Lindblad equation, the library includes a simple implementation of the Runge-Kutta4 algorithm for ODEs.
BackAction.rk4 — Functionrk4(f, y0, tspan, nsteps)Arguments
f::Function: function $f(t, y)$ defininf the system of ODEsy0::Vector{Float}: inital conditiontspan::Tuple{Float64}: initial and final timensteps::Int: number of steps.
Returns
An array Array{typeof(y0[1])} with dimensions (ndims(y0), nsteps) with the values of $y$ at each step.