qit.seq.Seq

class qit.seq.Seq(tau=None, control=None, name='')

Piecewise constant control sequences for quantum systems.

Parameters

• tau (array[float]) – durations of the time slices

• control (array[float]) – control[i, j] is the value of control field j during time slice i. shape == (len(tau), len(B)).

• name (str) – name of the sequence

The total generator for the time slice j is given by

$$G_j=A+\sum _k{\text{control}}_{jk}{B}_k,$$

and the corresponding propagator is

$$P_j=\exp ({\tau }_j{G}_j).$$

Attributes

name	name of the sequence
A	drift generator (typically $-i/\hslash$ times a Hamiltonian and a time unit of your choice)
B	control generators
tau	durations of the time slices
control	control field values for each time slice

Methods

generator(j)	Generator for time slice j.
to_prop()	Propagator corresponding to the control sequence.

name

name of the sequence

Type

str

A

drift generator (typically $-i/\hslash$ times a Hamiltonian and a time unit of your choice)

Type

array

B

control generators

Type

list[array]

tau

durations of the time slices

Type

array[float]

control

control field values for each time slice

Type

array[float]

generator(j)

Generator for time slice j.

Parameters

j (int) – time slice index

Returns

antihermitian generator for the given time slice

Return type

array[complex]

to_prop()

Propagator corresponding to the control sequence.

Returns the propagator matrix corresponding to the action of the control sequence.

Governing equation: $\dot{(}X)(t)=(A+\sum _k{u}_k(t)B_k)X(t)=G(t)X(t)$.