Pulse Class¶

class pynlo.light.Pulse(frep_MHz=None, n=None)[source]¶

Class which carried all information about the light field. This class is a base upon which various cases are built (eg analytic pulses, CW fields, or pulses generated from experimental data.)

AT¶

Property: time-domain electric field grid

Returns:	AT – Complex electric field in time domain.
Return type:	ndarray, shape NPTS

AW¶

Property: frequency-domain electric field grid

Returns:	AW – Complex electric field in frequency domain.
Return type:	ndarray, shape NPTS

T_mks¶

Property: time grid

Returns:	T_mks – Time grid corresponding to AT [s]
Return type:	ndarray, shape NPTS

T_ps¶

Property: time grid

Returns:	T_ps – Time grid corresponding to AT [ps]
Return type:	ndarray, shape NPTS

V_THz¶

Property: relative angular frequency grid

Returns:	V_THz – Relative angular frequency grid corresponding to AW [THz]
Return type:	ndarray, shape NPTS

V_mks¶

Property: relative angular frequency grid

Returns:	V_mks – Relative angular frequency grid corresponding to AW [Hz]
Return type:	ndarray, shape NPTS

W_THz¶

Property: angular frequency grid

Returns:	W_THz – Angular frequency grid corresponding to AW [THz]
Return type:	ndarray, shape NPTS

W_mks¶

Property: angular frequency grid

Returns:	W_mks – Angular frequency grid corresponding to AW [Hz]
Return type:	ndarray, shape NPTS

add_time_offset(offset_ps)[source]¶: Shift field in time domain by offset_ps picoseconds. A positive offset moves the pulse forward in time.

calc_epp()[source]¶

Calculate and return energy per pulse via numerical integration of \(A^2 dt\)

Returns:	x – Pulse energy [J]
Return type:	float

calculate_intensity_autocorrelation()[source]¶

Calculates and returns the intensity autocorrelation, \(\int P(t)P(t+\tau) dt\)

Returns:	x – Intensity autocorrelation. The grid is the same as the pulse class’ time grid.
Return type:	ndarray, shape N_pts

center_frequency_THz¶

Property: center frequency

Returns:	center_frequency_THz – Frequency of center point in AW grid [THz]
Return type:	float

center_frequency_mks¶

Property: center frequency

Returns:	center_frequency_mks – Frequency of center point in AW grid [Hz]
Return type:	float

center_wavelength_mks¶

Property: center wavelength

Returns:	center_wavelength_mks – Wavelength of center point in AW grid [m]
Return type:	float

center_wavelength_nm¶

Property: center wavelength

Returns:	center_wavelength_nm – Wavelength of center point in AW grid [nm]
Return type:	float

chirp_pulse_W(GDD, TOD=0, FOD=0.0, w0_THz=None)[source]¶

Alter the phase of the pulse

Apply the dispersion coefficients \(\beta_2, \beta_3, \beta_4\) expanded around frequency \(\omega_0\).

Parameters:	GDD (float) – Group delay dispersion (\(\beta_2\)) [ps^2] TOD (float, optional) – Group delay dispersion (\(\beta_3\)) [ps^3], defaults to 0. FOD (float, optional) – Group delay dispersion (\(\beta_4\)) [ps^4], defaults to 0. w0_THz (float, optional) – Center frequency of dispersion expansion, defaults to grid center frequency.

Notes

The convention used for dispersion is

\[E_{new} (\omega) = \exp\left(i \left( \frac{1}{2} GDD\, \omega^2 + \frac{1}{6}\, TOD \omega^3 + \frac{1}{24} FOD\, \omega^4 \right)\right) E(\omega)\]

clone_pulse(p)[source]¶: Copy all parameters of pulse_instance into this one

create_cloned_pulse()[source]¶: Create and return new pulse instance identical to this instance.

create_subset_pulse(center_wl_nm, NPTS)[source]¶: Create new pulse with smaller frequency span, centered at closest grid point to center_wl_nm, with NPTS grid points and frequency-grid values from this pulse.

dF_THz¶

Property: frequency grid spacing

Returns:	dF_ps – Frequency grid spacing [ps]
Return type:	float

dF_mks¶

Property: frequency grid spacing

Returns:	dF_mks – Frequency grid spacing [s]
Return type:	float

dT_mks¶

Property: time grid spacing

Returns:	dT_mks – Time grid spacing [s]
Return type:	float

dT_ps¶

Property: time grid spacing

Returns:	dT_ps – Time grid spacing [ps]
Return type:	float

frep_MHz¶

Property: Repetition rate. Used for calculating average beam power.

Returns:	frep_MHz – Pulse repetition frequency [MHz]
Return type:	float

frep_mks¶

Property: Repetition rate. Used for calculating average beam power.

Returns:	frep_mks – Pulse repetition frequency [Hz]
Return type:	float

rotate_spectrum_to_new_center_wl(new_center_wl_nm)[source]¶: Change center wavelength of pulse by rotating the electric field in the frequency domain. Designed for creating multiple pulses with same gridding but of different colors. Rotations is by integer and to the closest omega.

set_AT(AT_new)[source]¶

Set the value of the time-domain electric field.

Parameters:	AW_new (array_like) – New electric field values.

set_AW(AW_new)[source]¶

Set the value of the frequency-domain electric field.

Parameters:	AW_new (array_like) – New electric field values.

set_NPTS(NPTS)[source]¶

Set the grid size.

The actual grid arrays are not altered automatically to reflect a change.

Parameters:	NPTS (int) – Number of points in grid

set_center_wavelength_m(wl)[source]¶

Set the center wavelength of the grid in units of meters.

Parameters:	wl (float) – New center wavelength [m]

set_center_wavelength_nm(wl)[source]¶

Set the center wavelength of the grid in units of nanometers.

Parameters:	wl (float) – New center wavelength [nm]

set_epp(desired_epp_J)[source]¶

Set the energy per pulse (in Joules)

Parameters:	desired_epp_J (float) – the value to set the pulse energy [J]
Returns:
Return type:	nothing

set_frep_MHz(fr_MHz)[source]¶

Set the pulse repetition frequency.

This parameter used internally to convert between pulse energy and average power.

Parameters:	fr_MHz (float) – New repetition frequency [MHz]

set_frequency_window_THz(DF)[source]¶

Set the total frequency window of the grid.

This sets the grid dF, and implicitly changes the temporal span (~1/dF).

Parameters:	DF (float) – New grid time span [THz]

set_frequency_window_mks(DF)[source]¶

Set the total frequency window of the grid.

This sets the grid dF, and implicitly changes the temporal span (~1/dF).

Parameters:	DF (float) – New grid time span [Hz]

set_time_window_ps(T)[source]¶

Set the total time window of the grid.

This sets the grid dT, and implicitly changes the frequency span (~1/dT).

Parameters:	T (float) – New grid time span [ps]

set_time_window_s(T)[source]¶

Set the total time window of the grid.

This sets the grid dT, and implicitly changes the frequency span (~1/dT).

Parameters:	T (float) – New grid time span [s]

time_window_mks¶

Property: time grid span

Returns:	time_window_mks – Time grid span [ps]
Return type:	float

time_window_ps¶

Property: time grid span

Returns:	time_window_ps – Time grid span [ps]
Return type:	float

wl_mks¶

Property: Wavelength grid

Returns:	wl_mks – Wavelength grid corresponding to AW [m]
Return type:	ndarray, shape NPTS

wl_nm¶

Property: Wavelength grid

Returns:	wl_nm – Wavelength grid corresponding to AW [nm]
Return type:	ndarray, shape NPTS

write_frog(fileloc='broadened_er_pulse.dat', flip_phase=True)[source]¶

Save pulse in FROG data format. Grid is centered at wavelength center_wavelength (nm), but pulse properties are loaded from data file. If flip_phase is true, all phase is multiplied by -1 [useful for correcting direction of time ambiguity]. time_window (ps) sets temporal grid size.

power sets the pulse energy: if power_is_epp is True then the number is pulse energy [J] if power_is_epp is False then the power is average power [W], and is multiplied by frep to calculate pulse energy