I am playing around with an Experiment that involves dressed spins. This boils down to a z-modulation of the external Field in the rf-Region, while spin-Locking the electron spin.
Do you have any suggestions regarding an implementation in Spinach? I would definitely like to keep the static Hamiltonian during the spin-lock, and not just use omega_1*Sx. For the rf-Part, I suspect that a rotating-frame approximation will fail, because the nutation frequency is in the range of the “dressed resonance frequency”.
I looked around in the examples but didn’t find a suiting one. Regarding the shaped_pulse_af() function I would not know how to include two frequencies and amplitudes.
Dressed spin simulations
Re: Dressed spin simulations
The best function to use is shaped_pulse_xy - although the name seems to suggest that it only does X and Y, it actually supports an arbitrary number of operators and time-dependent coefficients. So having a Z operator with its own shape is not a problem. This solves your multiple frequency and amplitude problem -- you can specify as many operators and waveforms as you like.
Specify the static Hamiltonian as the drift, a cell array of operators that represent your interactions, and a cell array of their time dependencies. That should be it!
Not using the rotating frame would be a very expensive proposition -- your time step would have to be in the picoseconds, and all the pulse waveforms would have to be digitized at their full carrier frequency! I would recommend that you look at the following functions that perform numerical interaction representation transformations to arbitrary order: rotframe (simple) and intrep (low-level). Electron rotating frame not actually working is a very rare situation in EPR -- I am pretty sure that at least the static Lz from the magnet can be rotated away.
Specify the static Hamiltonian as the drift, a cell array of operators that represent your interactions, and a cell array of their time dependencies. That should be it!
Not using the rotating frame would be a very expensive proposition -- your time step would have to be in the picoseconds, and all the pulse waveforms would have to be digitized at their full carrier frequency! I would recommend that you look at the following functions that perform numerical interaction representation transformations to arbitrary order: rotframe (simple) and intrep (low-level). Electron rotating frame not actually working is a very rare situation in EPR -- I am pretty sure that at least the static Lz from the magnet can be rotated away.