bicks package

Submodules

bicks.bicsearch module

class bicks.bicsearch.FindBICs(phcs, num, mode='E', Nq=250)

Bases: object

find BICs in q-k0 space with single polarization.

  • Parameters

    • phcs (PhotonicCrystalSlab) – the Photonic Crystal Slab which is a kind of class.

    • num (EssentialNumber) –

    • mode ({"E", "H",}, optional) – considered mode

    • Nq (int, optional) – number which we divided half of the Brillouin into

dynamicplot(save=False)

show bics in the k-omega space with variant h.

  • Parameters

    save (str, optional) – the path to save the dynamic picture.

getcoeffs()

get the ratio of coefficients of two Bloch waves in opposite direction.

run(hstart, hend, Nh=20, limit=0.999)

search BICs by varying thickness of PhC slab.

  • Parameters

    • hstart (float) – start searching in this thickness

    • hend (float) – end searching in this thickness

    • Nh (int, optional) – number of searching thickness

    • limit (float) – the precision of judging if a point in q-k0 space is a BIC

showbic(i=0)

show bics in the k-omega space for one particular h.

  • Parameters

    i (int, optional) – the serial number of bic_hs

class bicks.bicsearch.FindBICsMix(phcs, num, qa, k0range=3.141592653589793, Nk0=200)

Bases: object

find BICs in ky-k0 space with mix polarization.

  • Parameters

    • phcs (PhotonicCrystalSlab) –

    • num (EssentialNumber) –

    • qa (float) – the Bloch wave number, in unit 1/a

    • k0range (float, option) – the length of the range of k0, in unit 1/a

    • Nk0 (int, optional) – the number which we divided the k0range

run(limit=0.999)

get the BICs.

  • Parameters

    limit (float) – the precision of judging if a point in q-k0 space is a BIC

showbic()

show bics in the k-omega space.

bicks.boundryconditionwithcTIR module

bicks.boundryconditionwithcTIR.getcoemix(real_fields, imag_fields, num, constant_number=2)

For the mix mode(both E and H mode)

  • Parameters

    • real_fields (list[FieldInPhCS]) – the fields from eigenstates with real kz

    • imag_fields (list[FieldInPhCS]) – the fields from eigenstates with imaginary kz

    • num (EssentialNumber) –

    • constant_number (int, optional) – the serial number of columm of extend matricx which represents constant in eqs.

  • Returns

    • list[float] – the ratio of coefficients of two Bloch waves in opposite direction(the tangential compoments of E are even in z direction).

    • list[float] – the ratio of coefficients of two Bloch waves in opposite direction(the tangential compoments of E are odd in z direction).

    • list[float] – real kz of all Bloch waves

bicks.boundryconditionwithcTIR.getcoesingle(real_fields, imag_fields, num, constant_number=0)

For the single mode(only E or H mode)

  • Parameters

    • real_fields (list[FieldInPhCS]) – the fields from eigenstates with real kz

    • imag_fields (list[FieldInPhCS]) – the fields from eigenstates with imaginary kz

    • num (EssentialNumber) –

    • constant_number (int, optional) – the serial number of columm of extend matricx which represents constant in eqs.

  • Returns

    • list[float] – ratio of coefficients of two Bloch waves in opposite direction(the tangential compoments of E are even in z direction).

    • list[float] – ratio of coefficients of two Bloch waves in opposite direction(the tangential compoments of E are odd in z direction).

    • list[float] – real kz of all Bloch waves

bicks.boundryconditionwithcTIR.singleboundary(real_fields, imag_fields, num, constant_number=0)

compute the reflection coefficients on the single boundary(not the slab)

  • Parameters

    • real_fields (list[FieldInPhCS]) – the fields from eigenstates with real kz

    • imag_fields (list[FieldInPhCS]) – the fields from eigenstates with imaginary kz

    • num (EssentialNumber) –

    • constant_number (int, optional) – the serial number of columm of extend matricx which represents constant in eqs.

  • Returns

    ratio of coefficients of two Bloch waves in opposite direction(the tangential compoments of E are even in z direction).

  • Return type

    list[float]

bicks.crystalandnumber module

class bicks.crystalandnumber.EssentialNumber(n_radiation=1, nimag_plus=0, n_propagation=0)

Bases: object

Some essential number of modes or orders.

ne()

number of diffraction orders(negetive).

  • Type

    int(>0)

po()

number of diffraction orders(positive).

  • Type

    int(>0)

d()

number of diffraction orders.

  • Type

    int(>0)

r()

number of radiation channels in air.

  • Type

    int(>0)

listr()

radiation channels orders.

  • Type

    np.ndarray(dtype=np.int)

real()

number of considered real kz.

  • Type

    int(>0)

imag()

number of considered imag kz.

  • Type

    int(>=0)

modes()

number of considered kz; modes = real + imag.

  • Type

    int(>=0)

class bicks.crystalandnumber.PhotonicCrystalSlab(epsilon, fillingrate, mu=array([1, 1]), thickness=1.0, periodlength=1)

Bases: object

Here, we defined a class named PhotonicCrystalSlab which is 1D. Warning! The structure is non-magnetic.

h()

thickness of the PC slab.

  • Type

    float

ep()

a list which contains the dielectric constant of the two different layers; [small, big], for example, [1.0, 4.9]

  • Type

    list

fr()

filling ratio (fill the small dielectric constant medium).

  • Type

    float

a()

the length of a period.

  • Type

    float

show()

Show the PhC slab in a picture.

bicks.eigenkpar module

bicks.eigenkpar.find_eigen_kpar(phcs, k0a, qa, nmode, mode='E')

The eigenstates of the 1D photonic crystal.

phcs: PhotonicCrystalSlab

the Photonic Crystal Slab which is a kind of class.

qa: float

the Bloch wave number

k0a: float

the frequency divided by (2pi\*c)

nmode: int

the number of considered Bloch modes

mode: {“E”, “H”}, optional

the mode of the eigenstate

  • Returns

    • np.ndarray – real k_parallels(eigenvalue) of eigenstates

    • np.ndarray – imaginary k_parallels(eigenvalue) of eigenstates

bicks.eigenkpar.find_eigen_kpar_in_an_area(phcs, qa, k0a, num, kpara_real_extreme, kpara_imag_extreme, mode='E')

The eigenstates of the 1D photonic crystal.

phcs: PhotonicCrystalSlab

the Photonic Crystal Slab which is a kind of class.

qa: float

the Bloch wave number

k0a: float

the frequency divided by (2pi\*c)

num: EssentialNumber kpara_real_extreme: list[float]

there is a real eigenvalue between any the adjacent two in this list

kpara_imag_extreme: list[float]

there is an imaginary eigenvalue between any the adjacent two in this
list

mode: {“E”, “H”}, optional

the mode of the eigenstate

  • Returns

    • np.ndarray – real k_parallels(eigenvalue) of eigenstates

    • np.ndarray – imaginary k_parallels(eigenvalue) of eigenstates

bicks.field module

class bicks.field.BulkEigenStates(phcs, k0a, kpar, qa, mode='E', normalization=1)

Bases: object

The eigenstates i.e. periodic parts of fields in PhC

Fourier_coefficients(i)

u(xra)

v(xra)

w(xra)

class bicks.field.FieldInPhcS(eigenstate, kya=0)

Bases: object

The field generated by a BulkEigenStates in PhC.

Ex(x, z, kzdirection=0)

Ey(x, z, kzdirection=0)

Hx(x, z, kzdirection=0)

Hy(x, z, kzdirection=0)

fieldfc(i, field_compoments)

without the basis

show(fieldcomponent, oprator, Nx=20)

unit in period a

class bicks.field.FieldsWithCTIRInArea(phcs, num, k0a, qa, kya, real_parallel, imag_parallel, mode='E')

Bases: object

The class can get the coefficinents of different fields when the cTIR happends on the upper boundry in specific q-k0 area dicided by EssentialNumber num.

class bicks.field.FieldsWithCTIRMix(phcs, num, k0a, qa, kya, kpe, kph)

Bases: object

bicks.mathtool module

bicks.mathtool.dichotomy(f, a, b, epsilon=1e-05)

Tradional dichotomy to find a root of a function

bicks.mathtool.find_all_peaks(f, x_start, x_end, deltax=0.01, eps=0.001, lastdata=[])

bicks.mathtool.find_n_roots(f, n, deltax, eps=1e-10)

Warning! Don’t make the deltax = 0.1

bicks.mathtool.find_n_roots_for_small_and_big_q(f, qa, n, gox=0, deltax=0.024, eps=1e-10, peak1=0)

bicks.mathtool.find_proj_roots(f, endk0, startk0=0.121, deltak0=0.12, eps=1e-10)

bicks.mathtool.find_real_roots(f, endkz, startkz=0, deltakz=0.12, eps=1e-10)

bicks.mathtool.find_real_roots_for_small_and_big_q(f, qa, deltax=0.024, eps=1e-10)

bicks.mathtool.golden_section(f, a, b, epsilon=1e-10)

bicks.mathtool.minus_cosqa(x)

bicks.mathtool.secant(f, a, b, eps=1e-05)

bicks.photoniccrystalbandprojection module

bicks.photoniccrystalbandprojection.find_band_projection(phcs, num, Nq=100, mode='E')

find the area where we can use dichotomy to find roots(kz).

phcs: PhotonicCrystalSlab

the Photonic Crystal Slab which is a kind of class.

num: EssentialNumber mode: {“E”, “H”}, optional

the mode of the eigenstate

Nq: int, optional

number which we divided half of Brillouin into

  • Returns

    • k0_floor (np.ndarray) – real k_parallels of eigenstates

    • imag_k_parallel (np.ndarray) – imag k_parallels of eigenstates

bicks.photoniccrystalbandprojection.mini_frequncy(phcs, num, qa, deltak0)

Find the floor of frequncy range for a specific q where the number of real k is a constant which is a paramter.

phcs: PhotonicCrystalSlab num: EssentialNumber

  • Returns

    k0_floor – the floor of range of k0 where the number of real k is a constant.

  • Return type

    np.ndarray

Module contents