triqs::operators::canonical_ops_t

#include <triqs/operators/many_body_operator.hpp>

Detailed Description

Second quantization creation/annihilation operator.

A canonical second quantization operator, \( \hat{c}_{\alpha_i} \) or \( \hat{c}_{\alpha_i}^\dagger \), is defined by

• a single particle state index \( \alpha_i = (\beta^{(i)}_1, \dots, \beta^{(i)}_{k_i}) \), where each \( \beta^{(i)}_j \) is an integer, a string, a double or an array of integers, and
• a boolean flag dagger indicating whether it is a creation (true) or annihilation (false) operator.

Definition at line 87 of file many_body_operator.hpp.

Public Member Functions
void	deserialize (auto &ar)
	Deserialize the canonical operator from a generic archive.
auto	operator<=> (canonical_ops_t const &b) const
	Three-way comparison operator for canonical operators.
bool	operator== (canonical_ops_t const &b) const
	Equality operator for canonical operators.
void	serialize (auto &ar) const
	Serialize the canonical operator to a generic archive.

Public Attributes
bool	dagger {false}
	True for creation ( \( \hat{c}_{\alpha_i}^{\dagger} \)), false for annihilation ( \( \hat{c}_{\alpha_i} \)) operators.
indices_t	indices {}
	Single particle state index \( \alpha_i \).

Member Function Documentation

deserialize()

void triqs::operators::canonical_ops_t::deserialize ( auto & ar )

inline

Deserialize the canonical operator from a generic archive.

Parameters

ar	Archive to deserialize from.

Definition at line 161 of file many_body_operator.hpp.

operator<=>()

auto triqs::operators::canonical_ops_t::operator<=> ( canonical_ops_t const & b ) const

inline

Three-way comparison operator for canonical operators.

The ordering is defined as follows:

• All creation operators are less than all annihilation operators, i.e. \( \hat{c}_{\alpha_i}^\dagger < \hat{c}_{\alpha_j} \) for any \( \alpha_i \) and \( \alpha_j \).
• Among canonical operators with the same dagger flag, indices are compared element-wise. For each element, the active type of std::variant is compared first (long < std::string < double < std::array<long, 3>), and only when the active types agree are the underlying values compared.
• For annihilation operators, the index comparison is reversed, so that with the same set of indices the ordering becomes \( \hat{c}_{\alpha_1}^\dagger < \hat{c}_{\alpha_2}^\dagger < \dots < \hat{c}_{\alpha_2} < \hat{c}_{\alpha_1} \). For example, with integer indices \( 1, 2, 3 \) the ascending order is \(\hat{c}_1^\dagger < \hat{c}_2^\dagger < \hat{c}_3^\dagger < \hat{c}_3 < \hat{c}_2 < \hat{c}_1 \).

Note

The order induced by this operator is in general different from the order in triqs::hilbert_space::fundamental_operator_set.

Parameters

b	Right hand side operator.

Returns

std::strong_ordering result of the comparison.

Definition at line 117 of file many_body_operator.hpp.

operator==()

bool triqs::operators::canonical_ops_t::operator== ( canonical_ops_t const & b ) const

inline

Equality operator for canonical operators.

Parameters

b	Right hand side operator.

Returns

True if both operators are creation (annihilation) operators with the same indices, false otherwise.

Definition at line 149 of file many_body_operator.hpp.

serialize()

void triqs::operators::canonical_ops_t::serialize ( auto & ar ) const

inline

Serialize the canonical operator to a generic archive.

Parameters

ar	Archive to serialize to.

Definition at line 155 of file many_body_operator.hpp.

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

• triqs/operators/many_body_operator.hpp