each node corresponds to a certain state (see the cen-
tral part of figure 1).
If the base states of the qubit are denoted as
|
0
i
(ket vector with coordinates (1, 0), which describes
the spin direction of the quantum particle against the
external field) and
|
1
i
(ket vector with coordinates
(0, 1), which describes the spin direction of a quan-
tum particle along an external field), then any other
state from the set of possible states will be determined
by the relation (linear combination, superposition):
α
|
0
i
+ β
|
1
i
,
where α and β are complex numbers that satisfy the
relation
|
α
|
2
+
|
β
|
2
= 1;
|
α
|
2
and
|
β
|
2
represent prob-
ability amplitudes of transition to the states
|
0
i
and
|
1
i
.
Qubits can be connected (entangled) with each
other. This means that a connection can be estab-
lished between them, as a result of which each time
changing the state of one of several qubits, the rest
change in accordance with it, and the set of entan-
gled qubits is interpreted as a filled quantum regis-
ter. Like a single qubit, the quantum register is much
more complex than the classical bit register. It is able
not only to be in all possible combinations of its con-
stituent bits but also to implement subtle relationships
between them, which significantly increases the com-
putational power of systems based on qubits.
In the state of entanglement and superposition,
qubits represent a quantum register. During calcula-
tions in the quantum register, the amplitudes of qubits
(
|
α
|
2
and
|
β
|
2
) are arranged in such a way that pos-
itive values of the amplitude of one qubit neutralize
the negative amplitudes of another qubit, and com-
putational errors are canceled (positive amplitudes of
qubits, on the contrary, amplify each other). This
is how the scenario of getting the correct answer is
formed.
Explaining the differences in the principles of
classical and quantum computers, teachers turn to the
problem of finding a way out of the maze, using the
example of which they illustrate and convince that the
classical computer consistently goes through all ways,
hitting a dead end once at once, but the quantum com-
puter can check all possible variants at once (Sigov
et al., 2019). Next, teachers focus attention and inter-
est, especially of bright and inquisitive students, on
the fact that the main engineering complexity of the
implementation of quantum processor registers is to
maintain the state of superposition and entanglement
of qubits during calculations (measurements) – coher-
ence time.
The calculations in a quantum computer are per-
formed using quantum algorithms. It is proposed to
be understood as an algorithm containing a finite se-
quence of unitary (reversible) operations/gates with
an indication of the qubits on which they need to be
performed. The correctness of the calculation result
using the corresponding quantum algorithm is deter-
mined with a certain probability. To increase the prob-
ability of getting a correct outcome in quantum algo-
rithms, the multiplicity of operations is especially in-
creased, which are selected in such a way that incor-
rect results are mutually destroyed with a high proba-
bility, and the probability of a correct result increases.
The last section – “Basic quantum algorithms and
their implementation on circuits and using a program-
ming language” – is the second main section of the
sample module, because the expected results of mas-
tering it that the student:
• knows the particularities of the implementation of
quantum algorithms in an environment with re-
mote access and a local one; the basics of the
syntax of quantum algorithm implementation by
a general-purpose programming language;
• understands the basic concepts of quantum algo-
rithms;
• explains the step-by-step structure of basic quan-
tum algorithms;
• uses the capabilities of remote and/or local access
environment to implement quantum algorithms in
the form of circuits and programs;
• implements and executes basic quantum algo-
rithms in a special environment using a general-
purpose programming language and the graphical
editor;
• is aware of the effectiveness of quantum comput-
ing in comparison with classical ones;
• evaluates the compliance of the results of the pro-
gram with the task at hand;
• follows the rules for writing readable code and
comments to it, explains the code to others;
• checks, hypothesizes, critically evaluates, identi-
fies the shortcomings of the implemented algo-
rithms.
Problems that can be solved with the help of quan-
tum computers can also be solved on the computa-
tional basis of classical computers. However, the ad-
vantage of quantum computers, or more precisely,
quantum algorithms (Zahorodko et al., 2021), is to re-
duce the time spent on solving the problem by par-
allelizing operations through the generation of en-
tangled quantum states and their further use. Such
cases are called quantum acceleration. The applica-
tion of quantum acceleration is the most advantageous
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