squander::density::AmplitudeDampingChannel Class Reference

Amplitude damping (T1 relaxation): |1⟩ → |0⟩ decay. More...

#include <noise_channel.h>

Inheritance diagram for squander::density::AmplitudeDampingChannel:

Public Member Functions
	AmplitudeDampingChannel (int target_qbit, double gamma)
	Constructor. More...
void	apply (DensityMatrix &rho) override
	Apply noise channel to density matrix. More...
double	get_gamma () const
std::string	get_name () const override
	Get channel name. More...
int	get_target_qbit () const

Private Attributes
double	gamma_
	γ = 1 - exp(-t/T1) More...
int	target_qbit_

Detailed Description

Amplitude damping (T1 relaxation): |1⟩ → |0⟩ decay.

Models energy relaxation from excited state to ground state. Represents spontaneous emission in real quantum systems.

Kraus operators:

• K₀ = [[1, 0], [0, √(1-γ)]]
• K₁ = [[0, √γ], [0, 0]]

where γ = 1 - exp(-t/T1)

Example:

  AmplitudeDampingChannel t1_noise(0, 0.05);  // 5% amplitude damping on
qubit 0 DensityMatrix rho(2); t1_noise.apply(rho);

Definition at line 105 of file noise_channel.h.

Constructor & Destructor Documentation

AmplitudeDampingChannel()

squander::density::AmplitudeDampingChannel::AmplitudeDampingChannel	(	int	target_qbit,
		double	gamma
	)

Constructor.

Parameters

target_qbit	Target qubit index
gamma	Damping parameter γ = 1 - exp(-t/T1) ∈ [0, 1]

Exceptions

std::invalid_argument

if gamma not in [0,1]

Definition at line 72 of file noise_channel.cpp.

Member Function Documentation

apply()

void squander::density::AmplitudeDampingChannel::apply ( DensityMatrix &  rho )

overridevirtual

Apply noise channel to density matrix.

Parameters

rho	Density matrix (modified in-place)

Implements squander::density::NoiseChannel.

Definition at line 80 of file noise_channel.cpp.

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get_gamma()

double squander::density::AmplitudeDampingChannel::get_gamma ( ) const

inline

Definition at line 118 of file noise_channel.h.

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get_name()

std::string squander::density::AmplitudeDampingChannel::get_name ( ) const

inlineoverridevirtual

Get channel name.

Implements squander::density::NoiseChannel.

Definition at line 116 of file noise_channel.h.

get_target_qbit()

int squander::density::AmplitudeDampingChannel::get_target_qbit ( ) const

inline

Definition at line 119 of file noise_channel.h.

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Member Data Documentation

gamma_

double squander::density::AmplitudeDampingChannel::gamma_

private

γ = 1 - exp(-t/T1)

Definition at line 123 of file noise_channel.h.

target_qbit_

int squander::density::AmplitudeDampingChannel::target_qbit_

private

Definition at line 122 of file noise_channel.h.

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The documentation for this class was generated from the following files:

• noise_channel.h
• noise_channel.cpp