2D potentials#

Base classes#

class torchgpe.utils.potentials.Potential[source]#

Base class for potentials. It is not meant to be used directly, but to be inherited by other classes.

Attributes

`is_time_dependent`	Whether the potential is time dependent or not
`gas`	The `Gas` object to which the potential is applied

Methods

`set_gas`	Set the `Gas` object to which the potential is applied
`on_propagation_begin`	Called at the beginning of the propagation.

class torchgpe.utils.potentials.LinearPotential[source]#

Base class for linear 2D potentials. It is not meant to be used directly, but to be inherited by other classes.

Methods

get_potential

Return the linear potential evaluated on the grid.

class torchgpe.utils.potentials.NonLinearPotential[source]#

Base class for non-linear 2D potentials. It is not meant to be used directly, but to be inherited by other classes.

Methods

potential_function

Return the non-linear potential evaluated on the grid.

Implemented potentials#

2D specific potentials#

class torchgpe.bec2D.potentials.Zero[source]#: Zero potential. It is equivalent to not applying any potential at all.

class torchgpe.bec2D.potentials.Trap(omegax, omegay)[source]#

Harmonic trapping potential

Parameters:

omegax (Union[float, Callable]) – The frequency along the x axis of the harmonic oscillator. It can be set to be either a constant or a function of time.
omegay (Union[float, Callable]) – The frequency along the y axis of the harmonic oscillator. It can be set to be either a constant or a function of time.

class torchgpe.bec2D.potentials.Contact(a_s=100, a_orth=1e-06)[source]#

Contact interactions potential

Parameters:

a_s (float) – The scattering length in units of the Bohr radius.
a_orth (float) – The renormalization parameter for the scattering length to account for the missing third dimension.

class torchgpe.bec2D.potentials.Lattice(V0=0, lam=1e-06, theta=0, phi=0, w0=inf)[source]#

Lattice potential

Parameters:

V0 (Union[float, Callable]) – The lattice depth in units of the recoil energy. It can be set to be either a constant or a function of time.
lam (float) – The wave length of the lattice.
theta (float) – The angle of the lattice in the 2D plane.
phi (Union[float, Callable]) – The phase of the lattice.
w0 (float)

class torchgpe.bec2D.potentials.SquareBox(V, D)[source]#

Square box potential

Parameters:

V (float) – The depth of the box.
D (float) – The size of the box.

class torchgpe.bec2D.potentials.RoundBox(V, D)[source]#

Round box potential

Parameters:

V (float) – The depth of the box.
D (float) – The diameter of the box.

class torchgpe.bec2D.potentials.DispersiveCavity(lattice_depth, atomic_detuning, cavity_detuning, cavity_decay, cavity_coupling, cavity_angle=0, pump_angle=1.0471975511965976, waist=inf)[source]#

Transversally pumped dispersive cavity potential

Parameters:

lattice_depth (Union[float, Callable]) – The lattice depth in units of the recoil energy. It can be set to be either a constant or a function of time.
atomic_detuning (float) – The atomic frequency detuning with respect to the pump.
cavity_detuning (Union[float, Callable]) – The cavity’s frequency detuning with respect to the pump. It can be set to be either a constant or a function of time.
cavity_decay (float) – The cavity’s decay rate.
cavity_coupling (float) – The coupling constant between the gas and the cavity.
cavity_angle (float, optional) – The angle in the 2D plane of the cavity. Defaults to \(0\)
pump_angle (float, optional) – The angle in the 2D plane of the transversal pump. Defaults to \(\pi/3\)
waist (float, optional) – the waist of the gaussian beam. Defaults to infinity

Methods

`get_alpha`	Return the intracavity field
`get_order`	Return the order parameter for self-organization

Time dependent variables#

`time_dependent_variable`(var)	Transform a variable into a function of time
`any_time_dependent_variable`(*vars)	Check if any of the variables is time dependent
`linear_ramp`([v0, t0, v1, t1])	Implements a linear ramp from \(v_0\) to \(v_1\) between \(t_0\) and \(t_1\).
`s_ramp`([v0, t0, v1, t1])	Implements a smooth ramp from \(v_0\) to \(v_1\) between \(t_0\) and \(t_1\).
`quench`([v0, v1, quench_time])	Implements a quench from \(v_0\) to \(v_1\) at \(t=quench_time\).