SPDC

class spdcalc.spdcalc.SPDC

Bases: object

SPDC configuration object

This is the primary object that is used to hold the configuration of the SPDC process. There are two main ways to create an instance of this object:

1. By using the default constructor SPDC.default() which creates an instance with default values. These can then be modified as needed.

By using the SPDC.from_yaml(yaml: str) or SPDC.from_json(json: str)

Attributes Summary

`apodization`	The apodization
`counter_propagation`	Whether or not counter-propagation is used
`crystal_kind`	The type of crystal used in the SPDC process
`crystal_length_um`	The crystal length in micrometers
`crystal_phi_deg`	The crystal polar angle in degrees
`crystal_pm_type`	The phasematching type used in the SPDC process
`crystal_temperature_c`	The crystal temperature in degrees Celsius
`crystal_theta_deg`	The crystal azimuthal angle in degrees
`deff_pm_per_volt`	The effective nonlinear coefficient in pm/V
`idler_frequency_rad_per_s`	The idler frequency in radians per second
`idler_phi_deg`	The idler polar angle in degrees
`idler_theta_deg`	The idler (internal) azimuthal angle in degrees
`idler_theta_external_deg`	The idler external azimuthal angle in degrees
`idler_waist_position_um`	The idler waist position in micrometers
`idler_waist_um`	The idler waist in nanometers
`idler_wavelength_nm`	The idler wavelength in nanometers
`poling_period_um`	The poling period in micrometers
`pump_average_power_mw`	The pump average power in milliwatts
`pump_bandwidth_nm`	The pump spectral bandwidth in nanometers
`pump_frequency_rad_per_s`	The pump frequency in radians per second
`pump_spectrum_threshold`	The pump spectrum threshold
`pump_waist_nm`	The pump waist in nanometers
`pump_wavelength_nm`	The pump wavelength in nanometers
`signal_frequency_rad_per_s`	The signal frequency in radians per second
`signal_phi_deg`	The signal polar angle in degrees
`signal_theta_deg`	The signal (internal) azimuthal angle in degrees
`signal_theta_external_deg`	The signal external azimuthal angle in degrees
`signal_waist_position_um`	The signal waist position in micrometers
`signal_waist_um`	The signal waist in nanometers (x, y)
`signal_wavelength_nm`	The signal wavelength in nanometers

Methods Summary

`counts_coincidences`(si_range[, integrator])	Calculate the coincidence counts
`counts_singles_idler`(si_range[, integrator])	Calculate the singles rate for the idler
`counts_singles_signal`(si_range[, integrator])	Calculate the singles rate for the signal
`default`()	Create a new SPDC object with default values
`delta_k`(signal_frequency_rad_per_s, ...)	Compute delta_k vector
`efficiencies`(si_range[, integrator])	Calculate the efficiencies (symmetric, signal, idler)
`from_json`(json)	Create a new SPDC object from a JSON string
`from_yaml`(yaml)	Create a new SPDC object from a YAML string
`hom_rate_series`(time_delays, si_range[, ...])	Calculate the Hong-Ou-Mandel rate for different time delays
`hom_two_source_rate_series`(time_delays, si_range)	Calculate the two-source Hong-Ou-Mandel rate series
`hom_two_source_visibilities`(si_range[, ...])	Calculate the two-source Hong-Ou-Mandel visibilities
`hom_visibility`(si_range[, integrator])	Calculate the Hong-Ou-Mandel visibility
`joint_spectrum`([integrator])	Calculate the joint spectrum
`optimum_crystal_theta`()	Get the optimum crystal theta
`optimum_range`(n)	Get the optimum range in frequency space
`poling_domain_lengths_m`()	Get the poling domains as lengths in meters
`poling_domains`()	Get the poling domains
`to_json`()	Convert the SPDC object to a JSON string
`to_optimum`()	Convert this setup to an optimum setup
`to_yaml`()	Convert the SPDC object to a YAML string
`with_optimum_crystal_theta`()	Convert this setup to one with an optimum crystal theta
`with_optimum_idler`()	Convert this setup to one with an optimum idler
`with_optimum_periodic_poling`()	Convert this setup to one with an optimum periodic poling
`with_swapped_signal_idler`()	Swap the signal and idler

Attributes Documentation

apodization

The apodization

This is a dictionary with the following keys: - kind: the kind of apodization - parameter: the parameter depending on the kind

The kind can be one of the following: - off: no apodization - gaussian: Gaussian function (parameter: { fwhm_nm: float }) - bartlett: Bartlett function (parameter: float) - blackman: Blackman function (parameter: float) - connes: Connes function (parameter: float) - cosine: Cosine function (parameter: float) - hamming: Hamming function (parameter: float) - welch: Welch function (parameter: float) - interpolate: Interpolated evenly spaced points (parameter: list of floats)

counter_propagation: Whether or not counter-propagation is used

crystal_kind

The type of crystal used in the SPDC process

The values can be seen by looking at the id feilds from get_all_crystal_meta()

crystal_length_um: The crystal length in micrometers

crystal_phi_deg: The crystal polar angle in degrees

crystal_pm_type

The phasematching type used in the SPDC process

The format for setting this is flexible. The following are all valid: - “ooo” - “o-oo” - “Type2 e eo” - “type 2 e->eo”

crystal_temperature_c: The crystal temperature in degrees Celsius

crystal_theta_deg: The crystal azimuthal angle in degrees

deff_pm_per_volt: The effective nonlinear coefficient in pm/V

idler_frequency_rad_per_s: The idler frequency in radians per second

idler_phi_deg: The idler polar angle in degrees

idler_theta_deg: The idler (internal) azimuthal angle in degrees

idler_theta_external_deg: The idler external azimuthal angle in degrees

idler_waist_position_um: The idler waist position in micrometers

idler_waist_um: The idler waist in nanometers

idler_wavelength_nm: The idler wavelength in nanometers

poling_period_um: The poling period in micrometers

pump_average_power_mw: The pump average power in milliwatts

pump_bandwidth_nm: The pump spectral bandwidth in nanometers

pump_frequency_rad_per_s: The pump frequency in radians per second

pump_spectrum_threshold

The pump spectrum threshold

Values below this threshold are considered to be zero

pump_waist_nm: The pump waist in nanometers

pump_wavelength_nm: The pump wavelength in nanometers

signal_frequency_rad_per_s: The signal frequency in radians per second

signal_phi_deg: The signal polar angle in degrees

signal_theta_deg: The signal (internal) azimuthal angle in degrees

signal_theta_external_deg: The signal external azimuthal angle in degrees

signal_waist_position_um: The signal waist position in micrometers

signal_waist_um: The signal waist in nanometers (x, y)

signal_wavelength_nm: The signal wavelength in nanometers

Methods Documentation

counts_coincidences(si_range, integrator=None)

Calculate the coincidence counts

Parameters

si_rangeSIRange: Range of signal and idler frequencies
integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

float: The coincidence counts

counts_singles_idler(si_range, integrator=None)

Calculate the singles rate for the idler

Parameters

si_rangeSIRange: Range of signal and idler frequencies
integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

float: The singles rate for the idler

counts_singles_signal(si_range, integrator=None)

Calculate the singles rate for the signal

Parameters

si_rangeSIRange: Range of signal and idler frequencies
integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

float: The singles rate for the signal

static default(): Create a new SPDC object with default values

delta_k(signal_frequency_rad_per_s, idler_frequency_rad_per_s)

Compute delta_k vector

Parameters

signal_frequency_rad_per_sfloat: The signal frequency in rad/s
idler_frequency_rad_per_sfloat: The idler frequency in rad/s

Returns

tuple of float

efficiencies(si_range, integrator=None)

Calculate the efficiencies (symmetric, signal, idler)

Parameters

si_rangeSIRange: Range of signal and idler frequencies
integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

dict: The efficiencies (symmetric, signal, idler), and rates (coincidences, singles signal, singles idler)

static from_json(json): Create a new SPDC object from a JSON string

static from_yaml(yaml): Create a new SPDC object from a YAML string

hom_rate_series(time_delays, si_range, integrator=None)

Calculate the Hong-Ou-Mandel rate for different time delays

Parameters

time_delayslist of floats: The time delays in seconds
si_rangeSIRange: Range of signal and idler frequencies
integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

list of float: The Hong-Ou-Mandel rate for different time delays

hom_two_source_rate_series(time_delays, si_range, integrator=None)

Calculate the two-source Hong-Ou-Mandel rate series

Parameters

time_delayslist of floats: The time delays in seconds
si_rangeSIRange: Range of signal and idler frequencies
integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

dict: The two-source Hong-Ou-Mandel rate series

hom_two_source_visibilities(si_range, integrator=None)

Calculate the two-source Hong-Ou-Mandel visibilities

Parameters

si_rangeSIRange: Range of signal and idler frequencies
integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

dict: The two-source Hong-Ou-Mandel visibilities

hom_visibility(si_range, integrator=None)

Calculate the Hong-Ou-Mandel visibility

Parameters

si_rangeSIRange: Range of signal and idler frequencies
integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

dict: The Hong-Ou-Mandel visibility

joint_spectrum(integrator=None)

Calculate the joint spectrum

Parameters

integratorIntegrator, optional: The integrator to use, which defaults to a simple Simpson’s rule

Returns

JointSpectrum: The joint spectrum object

optimum_crystal_theta(): Get the optimum crystal theta

optimum_range(n): Get the optimum range in frequency space

poling_domain_lengths_m(): Get the poling domains as lengths in meters

Returns

List[Tuple[float, float]]

poling_domains()

Get the poling domains

They are a list of fractions of poling period

Returns

List[Tuple[float, float]]

to_json(): Convert the SPDC object to a JSON string

to_optimum(): Convert this setup to an optimum setup

to_yaml(): Convert the SPDC object to a YAML string

with_optimum_crystal_theta(): Convert this setup to one with an optimum crystal theta

with_optimum_idler(): Convert this setup to one with an optimum idler

with_optimum_periodic_poling(): Convert this setup to one with an optimum periodic poling

with_swapped_signal_idler(): Swap the signal and idler