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Quantum Computation
The Parameter-Shift Rule for Quantum Gates
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Install and load the QuantumFramework paclet:
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In the following circuit, the gate
R
x
(
θ
)
will be differentiated:
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[
2
]
:
=
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The corresponding expected value is:
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The gradient of
R
x
(
θ
)
is obtained with:
I
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[
4
]
:
=
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x
P
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2
(
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-
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[
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)
/
/
S
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[
4
]
=
-
S
i
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[
θ
]
The parameter–shift rule
only
works for gates of the form
θ
G
where
2
G
=
1
. In other cases that do not fulfill these conditions, the
stochastic parameter–shift rule
must be used
.
External Links
QuantumCircuitOperator
QuantumMeasurementOperator
Source Metadata
Citation:
Killoran, N. (2020, May 24). The stochastic parameter-shift rule. PennyLane Demos.
See Also
Wolfram/QuantumFramework
Publisher Information
Contributed by:
Sebastián Rodríguez, César Guerra
