ColdAtoms.jl Documentation

release_evolve(tspan, cord, atom_params, trap_params; eps=1e-3)

Simulates evolution of atoms after turning the trap off and recapture results

Input

• tspan – vector specifying the points of time for which output should be displayed
• cord – vector of initial coordiantes and velocities $[x,y,z,v_{x},v_{y},v_{z}]$
• atom_params – vector [atom mass in a.u., atom temperature in $\mu K$]
• trap_params – vector [trap depth $U_{0}$ in $\mu K$, beam waist radius in $\mu m$, beam Rayleigh length in $\mu m$]
• eps – (optional, default: 1e-3) cutoff to regularize Metropolis sampler, atoms that have energy over $U_{0}(1-eps)$ are considered to be out of trap

Output

Binary list of length tspan, which contains 1 at idx $i$ if atom is recaptured at tspan[i] and 0 otherwise

release_recapture(tspan, trap_params, atom_params, N; freq=10, skip=1000, eps=1e-3, harmonic=true)

Simulate release and recapture experiment to estimate atom's temperature.

Input

• tspan – vector specifying the points of time for which output should be displayed
• trap_params – vector [trap depth $U_{0}$ in $\mu K$, beam waist radius in $\mu m$, beam Rayleigh length in $\mu m$]
• atom_params – vector [atom mass in a.u., atom temperature in $\mu K$]
• N – number of Monte-Carlo samples, the same as number of atoms
• freq – (optional, default: 10) number of Metropolis steps skipped between samples to reduce sample dependency
• skip – (optional, default: 1000) number of Metropolis steps skipped before the Markov Chain is considered to reach stationary distribution
• eps – (optional, default: 1e-3) cutoff to regularize Metropolis sampler, atoms that have energy over $U_{0}(1-eps)$ are considered to be out of trap
• harmonic – (optional, default: true) uses harmonic approximation of gaussian beam if set to true, otherwise uses Metropolis sampler

Output

List of recapture probabilities corresponding to times in tspan and acceptance rate of Metropolis algorithm. If harmonic is set to true, acceptance rate is set to 1.0

simulation(
    tspan, ψ0, 
    atom_params,
    trap_params,
    samples,
    f,
    red_laser_phase_amplitudes,
    blue_laser_phase_amplitudes,
    red_laser_params,
    blue_laser_params,
    detuning_params,
    decay_params;
    atom_motion=true,
    free_motion=true,
    laser_noise=true,
    spontaneous_decay=true,
    parallel=false
    )

Simulate two-photon Rydberg excitation of single atom with several sources of decoherence

Input

• tspan – vector specifying the points of time for which output should be displayed
• ψ0 – initial wavefunction vector of normalized complex amplitudes $[c_{g}, c_{p}, c_{r}]$
• atom_params – vector [atom mass in a.u., atom temperature in $\mu K$]
• trap_params – vector [trap depth $U_{0}$ in $\mu K$, beam waist radius in $\mu m$, beam Rayleigh length in $\mu m$]
• samples – Monte-Carlo samples of initial atom coordinates and velocities, can be received using samples_generate
• f – frequencies at which laser phase noise is sampled
• red_laser_phase_amplitudes – amplitudes of red laser phase noise for correspoding frequencies f
• blue_laser_phase_amplitudes – amplitudes of blue laser phase noise for correspoding frequencies f
• red_laser_params – write explanation
• blue_laser_params – write explanation
• detuning_params – vector [Δ0, δ0], which sets detuning from intermediate level and Rydberg level correspondingly
• decay_params – write explanation
• atom_motion – (optional, default: true) if set to true, atom motion is included
• free_motion – (optional, default: true) if set to true, trap is turned off
• laser_noise – (optional, default: true) if set to true, laser phase noise is included
• spontaneous_decay – (optional, default: true) if set to true, spontaneous decay from intermediate level is included
• parallel – (optional, default: false) parallel implementation is under development
• n – (optional, default: 1) super-gauss parameter

Output

Outputs Monte-Carlo averaged density matrix and squared density matrix for error calculation with elements ordered in correspondence with order ground, intermediate, Rydberg