6.1. tnpy.model.TotalSz#

class tnpy.model.TotalSz(n)[source]#

Bases: tnpy.model.model_1d.Model1D

\[S_{tot}^z = \sum_{i=0}^{N-1} S_i^z\]
Parameters

n (int) – System size.

__init__(n)[source]#
\[S_{tot}^z = \sum_{i=0}^{N-1} S_i^z\]
Parameters

n (int) – System size.

Methods

__init__(n)

subsystem_mpo(partition_site)

Count the total \(S^z\) magnetization in subsystem A, without the other part of system B.

Attributes

mpo

Return matrix product operator (mpo) as a property of the model.

n

__init__(n)[source]#
\[S_{tot}^z = \sum_{i=0}^{N-1} S_i^z\]
Parameters

n (int) – System size.

subsystem_mpo(partition_site)[source]#

Count the total \(S^z\) magnetization in subsystem A, without the other part of system B. This can be useful for later calculation on the fluctuation of magnetization.

Parameters

partition_site (int) – The site to which the system is bipartite into A|B. The site itself is included in part A.

Return type

tnpy.operators.MatrixProductOperator

Returns:

References

1. H. Francis Song, Stephan Rachel, and Karyn Le Hur, General relation between entanglement and fluctuations in one dimension, Phys. Rev. B 82, 012405 (2010).