squander::density::NoiseOperation Class Reference

Base class for noise channel operations (CPTP maps). More...

#include <noise_operation.h>

Inheritance diagram for squander::density::NoiseOperation:

Public Member Functions
virtual void	apply_to_density (const double *params, int param_count, DensityMatrix &rho)=0
	Apply this operation to the density matrix. More...
virtual std::unique_ptr< IDensityOperation >	clone () const =0
	Create a deep copy of this operation. More...
virtual std::string	get_name () const =0
	Get operation name for debugging/display. More...
virtual int	get_parameter_num () const =0
	Get number of free parameters this operation requires. More...
bool	is_unitary () const override
	Check if this is a unitary operation (gate) or non-unitary (noise) More...

Detailed Description

Base class for noise channel operations (CPTP maps).

Noise channels are non-unitary quantum operations that model decoherence and errors. They are represented via Kraus operators: ρ → Σᵢ KᵢρKᵢ†

Unlike gates, noise channels:

• Cannot be represented as unitary matrices
• Generally decrease purity (mix the state)
• Preserve trace: Tr(ρ') = Tr(ρ) = 1

Definition at line 36 of file noise_operation.h.

Member Function Documentation

apply_to_density()

virtual void squander::density::IDensityOperation::apply_to_density ( const double *  params, int  param_count, DensityMatrix &  rho  )

pure virtualinherited

Apply this operation to the density matrix.

Parameters

params	Pointer to this operation's parameters (may be nullptr if param_count=0)
param_count	Number of parameters for this operation
rho	The density matrix to modify in-place

Implemented in squander::density::PhaseDampingOp, squander::density::AmplitudeDampingOp, squander::density::LocalDepolarizingOp, squander::density::DepolarizingOp, and squander::density::GateOperation.

clone()

virtual std::unique_ptr<IDensityOperation> squander::density::IDensityOperation::clone ( ) const

pure virtualinherited

Create a deep copy of this operation.

Returns

Unique pointer to the cloned operation

Implemented in squander::density::PhaseDampingOp, squander::density::AmplitudeDampingOp, squander::density::LocalDepolarizingOp, squander::density::DepolarizingOp, and squander::density::GateOperation.

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get_name()

virtual std::string squander::density::IDensityOperation::get_name ( ) const

pure virtualinherited

Get operation name for debugging/display.

Returns

Human-readable name (e.g., "H", "CNOT", "Depolarizing")

Implemented in squander::density::PhaseDampingOp, squander::density::AmplitudeDampingOp, squander::density::LocalDepolarizingOp, squander::density::DepolarizingOp, and squander::density::GateOperation.

get_parameter_num()

virtual int squander::density::IDensityOperation::get_parameter_num ( ) const

pure virtualinherited

Get number of free parameters this operation requires.

Returns

Number of parameters (0 for constant gates/fixed noise)

Implemented in squander::density::PhaseDampingOp, squander::density::AmplitudeDampingOp, squander::density::LocalDepolarizingOp, squander::density::DepolarizingOp, and squander::density::GateOperation.

is_unitary()

bool squander::density::NoiseOperation::is_unitary ( ) const

inlineoverridevirtual

Check if this is a unitary operation (gate) or non-unitary (noise)

Returns

true for unitary gates, false for noise channels

Implements squander::density::IDensityOperation.

Definition at line 38 of file noise_operation.h.

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

• noise_operation.h