Oscillator#

class scqubits.core.oscillator.Oscillator(E_osc, l_osc=None, truncated_dim=6, id_str=None)[source]#

Class representing a harmonic oscillator/resonator governed by a Hamiltonian \(H=E_\text{osc} a^{\dagger} a\), with \(a\) being the annihilation operator.

Parameters:

E_osc (float) – energy of the oscillator
l_osc (Optional[float]) – oscillator length (required to define phi_operator and n_operator)
truncated_dim (int) – desired dimension of the truncated quantum system; expected: truncated_dim > 1
id_str (Optional[str]) – optional string by which this instance can be referred to in HilbertSpace and ParameterSweep. If not provided, an id is auto-generated.

Return type:

QuantumSystemType

Methods

`Oscillator.__init__`(E_osc[, l_osc, ...])
`Oscillator.annihilation_operator`()	Returns the annihilation operator
`Oscillator.broadcast`(event, **kwargs)	Request a broadcast from CENTRAL_DISPATCH reporting event.
`Oscillator.create`()	Use ipywidgets to create a new class instance
`Oscillator.create_from_file`(filename)	Read initdata and spectral data from file, and use those to create a new SpectrumData object.
`Oscillator.creation_operator`()	Returns the creation operator
`Oscillator.default_params`()	Return dictionary with default parameter values for initialization of class instance
`Oscillator.deserialize`(io_data)	Take the given IOData and return an instance of the described class, initialized with the data stored in io_data.
`Oscillator.eigensys`([evals_count])	Returns array of eigenvalues and eigenvectors
`Oscillator.eigenvals`([evals_count])	Returns array of eigenvalues.
`Oscillator.filewrite`(filename)	Convenience method bound to the class.
`Oscillator.get_initdata`()	Returns dict appropriate for creating/initializing a new Serializable object.
`Oscillator.get_operator_names`()	Returns a list of all operator names for the quantum system.
`Oscillator.hilbertdim`()	Returns Hilbert space dimension
`Oscillator.matrixelement_table`(args, *kwargs)	rtype: `ndarray`
`Oscillator.n_operator`()	Returns the charge-number n operator defined as \(i (a^{\dagger} - a)/ ( \sqrt{2} l_\text{osc})\), with \(a\) representing an annihilation operator, and \(l_\text{osc}\) the oscillator length.
`Oscillator.phi_operator`()	Returns the phase operator defined as \(l_\text{osc} (a + a^{\dagger})/\sqrt{2}\), with \(a\) representing an annihilation operator, and \(l_\text{osc}\) the oscillator length.
`Oscillator.receive`(event, sender, **kwargs)	Receive a message from CENTRAL_DISPATCH and initiate action on it.
`Oscillator.serialize`()	Convert the content of the current class instance into IOData format.
`Oscillator.set_params`(**kwargs)	Set new parameters through the provided dictionary.
`Oscillator.set_params_from_gui`(change)	Set new parameters through the provided dictionary.
`Oscillator.supported_noise_channels`()	Returns a list of noise channels this QuantumSystem supports.
`Oscillator.widget`([params])	Use ipywidgets to modify parameters of class instance

Attributes

`E_osc`	Descriptor class for properties that are to be monitored for changes.
`id_str`
`l_osc`	Descriptor class for properties that are to be monitored for changes.
`truncated_dim`	Descriptor class for properties that are to be monitored for changes.

annihilation_operator()[source]#

Returns the annihilation operator

Return type:: ndarray

broadcast(event, **kwargs)#

Request a broadcast from CENTRAL_DISPATCH reporting event.

Parameters:

event (str) – event name from EVENTS
**kwargs –

Return type:

None

classmethod create()#

Use ipywidgets to create a new class instance

Return type:: QuantumSystem

classmethod create_from_file(filename)#

Read initdata and spectral data from file, and use those to create a new SpectrumData object.

Returns:: new SpectrumData object, initialized with data read from file
Return type:: SpectrumData
Parameters:: filename (str) –

creation_operator()[source]#

Returns the creation operator

Return type:: ndarray

static default_params()[source]#

Return dictionary with default parameter values for initialization of class instance

Return type:: Dict[str, Any]

classmethod deserialize(io_data)#

Take the given IOData and return an instance of the described class, initialized with the data stored in io_data.

Return type:: TypeVar(SerializableType, bound= Serializable)
Parameters:: io_data (IOData) –

eigensys(evals_count=6)[source]#

Returns array of eigenvalues and eigenvectors

Parameters:: evals_count (int) – number of desired eigenvalues (default value = 6)
Return type:: Tuple[ndarray, ndarray]

eigenvals(evals_count=6)[source]#

Returns array of eigenvalues.

Parameters:: evals_count (int) – number of desired eigenvalues (default value = 6)
Return type:: ndarray

filewrite(filename)#

Convenience method bound to the class. Simply accesses the write function.

Return type:: None
Parameters:: filename (str) –

get_initdata()#

Returns dict appropriate for creating/initializing a new Serializable object.

Return type:: Dict[str, Any]

classmethod get_operator_names()#

Returns a list of all operator names for the quantum system. Note that this list omits any operators that start with “_”.

Parameters:: subsys – Class instance of quantum system
Return type:: List[str]
Returns:: list of operator names

hilbertdim()[source]#

Returns Hilbert space dimension

Return type:: int

n_operator()[source]#

Returns the charge-number n operator defined as \(i (a^{\dagger} - a)/ ( \sqrt{2} l_\text{osc})\), with \(a\) representing an annihilation operator, and \(l_\text{osc}\) the oscillator length.

Return type:: ndarray

phi_operator()[source]#

Returns the phase operator defined as \(l_\text{osc} (a + a^{\dagger})/\sqrt{2}\), with \(a\) representing an annihilation operator, and \(l_\text{osc}\) the oscillator length.

Return type:: ndarray

receive(event, sender, **kwargs)#

Receive a message from CENTRAL_DISPATCH and initiate action on it.

Parameters:

event (str) – event name from EVENTS
sender (DispatchClient) – original sender reporting the event
**kwargs –

Return type:

None

serialize()#

Convert the content of the current class instance into IOData format.

Return type:: IOData

set_params(**kwargs)#: Set new parameters through the provided dictionary.

set_params_from_gui(change)#: Set new parameters through the provided dictionary.

supported_noise_channels()#

Returns a list of noise channels this QuantumSystem supports. If none, return an empty list.

Return type:: List

widget(params=None)#

Use ipywidgets to modify parameters of class instance

Parameters:: params (Dict[str, Any] | None) –