List Impurity methods in the docs (#115)

* small fixes in impurity docstrings

* cleanup

* list the impurity methods in the docs

* fix citation

* change order of citations

* remove newline from `ImpurityHOTRG` docstring

* Added extra documentation to `ImpurityTRG` (#116)

* Added extra documentation

* Improved docs

* fix field annotations

* fix merge

---------

Co-authored-by: Jarid Piceu <jarid.piceu@ugent.be>

Author: VictorVanthilt

docs/src/assets/tnrkit.bib

@@ -103,28 +103,29 @@ @article{yangLoopOptimizationTensor2017
 }
 
 @article{kadohTensorNetworkAnalysis2019,
-  title = {Tensor network analysis of critical coupling in two dimensional $\varphi^{4}$ theory},
-  author = {Kadoh, Daisuke and Kuramashi, Yoshinobu and Nakamura, Yoshifumi and Sakai, Ryo and Takeda, Shinji and Yoshimura, Yusuke},
-  year = 2019,
-  month = may,
-  journal = {Journal of High Energy Physics},
-  volume = {2019},
-  number = {5},
-  eprint = {1811.12376},
+  title        = {Tensor network analysis of critical coupling in two dimensional $\varphi^{4}$ theory},
+  author       = {Kadoh, Daisuke and Kuramashi, Yoshinobu and Nakamura, Yoshifumi and Sakai, Ryo and Takeda, Shinji and Yoshimura, Yusuke},
+  year         = 2019,
+  month        = may,
+  journal      = {Journal of High Energy Physics},
+  volume       = {2019},
+  number       = {5},
+  eprint       = {1811.12376},
   primaryclass = {hep-lat},
-  pages = {184},
-  issn = {1029-8479},
-  doi = {10.1007/JHEP05(2019)184}
+  pages        = {184},
+  issn         = {1029-8479},
+  doi          = {10.1007/JHEP05(2019)184}
 }
 
-@article{moritaMultiimpurityMethodBondweighted2024,
-  title = {Multi-Impurity Method for the Bond-Weighted Tensor Renormalization Group},
-  author = {Morita, Satoshi and Kawashima, Naoki},
-  year = 2024,
-  month = nov,
-  number = {arXiv:2411.13998},
-  eprint = {2411.13998},
-  primaryclass = {cond-mat},
-  publisher = {arXiv},
-  doi = {10.48550/arXiv.2411.13998}
+@article{moritaMultiimpurityMethodBondweighted2025,
+  title   = {Multi-Impurity Method for the Bond-Weighted Tensor Renormalization Group},
+  author  = {Morita, Satoshi and Kawashima, Naoki},
+  year    = 2025,
+  month   = feb,
+  journal = {Physical Review B},
+  volume  = {111},
+  number  = {5},
+  issn    = {2469-9950, 2469-9969},
+  doi     = {10.1103/PhysRevB.111.054433},
+  langid  = {english}
 }

docs/src/index.md

@@ -26,6 +26,10 @@ Many common TNR schemes have already been implemented:
 * `c4vCTM` (c4v symmetric CTM)
 * `rCTM` (reflection symmetric CTM)
 
+**Impurity Methods**
+* [`ImpurityTRG`](@ref)
+* [`ImpurityHOTRG`](@ref)
+
 **3D cubic tensor networks**
 * [`ATRG_3D`](@ref) (anisotropic TRG)
 * [`HOTRG_3D`](@ref) (higher order TRG)

src/schemes/impurityhotrg.jl

@@ -7,7 +7,7 @@ Single impurity method for Higher-Order Tensor Renormalization Group (for 2nd or
     $(FUNCTIONNAME)(T, T_imp_order1_1, T_imp_order1_2, T_imp_order2)
 
 ### Running the algorithm
-    run!(::ImpurityHOTRG, trunc::TensorKit.TruncationSheme, stop::Stopcrit[, finalizer=default_Finalizer, finalize_beginning=true, verbosity=1])
+    run!(::ImpurityHOTRG, trunc::TensorKit.TruncationSheme, stop::Stopcrit[, finalizer=ImpurityHOTRG_Finalizer, finalize_beginning=true, verbosity=1])
 
 Each step rescales the lattice by a (linear) factor of 2
 
@@ -22,7 +22,6 @@ $(TYPEDFIELDS)
 
 ### References
 * [Morita et al 10.1016/j.cpc.2018.10.014 (2018)](@cite moritaCalculationHigherorderMoments2019)
-
 """
 mutable struct ImpurityHOTRG{E, S, TT <: AbstractTensorMap{E, S, 2, 2}} <: TNRScheme{E, S}
     "Cental Tensor"

src/schemes/impuritytrg.jl

@@ -7,7 +7,7 @@ Impurity method for Tensor Renormalization Group
     $(FUNCTIONNAME)(T, T_imp1, T_imp2, T_imp3, T_imp4)
 
 ### Running the algorithm
-    run!(::ImpurityTRG, trunc::TensorKit.TruncationSheme, stop::Stopcrit[, finalizer=default_Finalizer, finalize_beginning=true, verbosity=1])
+    run!(::ImpurityTRG, trunc::TensorKit.TruncationSheme, stop::Stopcrit[, finalizer=ImpurityTRG_Finalizer, finalize_beginning=true, verbosity=1])
 
 Each step rescales the lattice by a (linear) factor of √2
 
@@ -20,23 +20,42 @@ Each step rescales the lattice by a (linear) factor of √2
 
 $(TYPEDFIELDS)
 
+Illustration (with p the pure tensor, and the p fills in the rest of the lattice):
+```
+    p   p
+    |   |  
+p---1---2---p
+    |   |
+p---4---3---p
+    |   |
+    p   p
+```
+
 ### References
-* [Morita et. al. 10.48550/arXiv.2411.13998 (2024)](@cite moritaMultiimpurityMethodBondweighted2024)
-* [Nakamoto et. al. 10.1007/JHEP05(2019)184 (2019)](@cite kadohTensorNetworkAnalysis2019)
+* [Kadoh et. al. 10.1007/JHEP05(2019)184 (2019)](@cite kadohTensorNetworkAnalysis2019)
+* [Morita et. al. Phys. Rev. B 111 (2025)](@cite moritaMultiimpurityMethodBondweighted2025)
 """
 mutable struct ImpurityTRG{E, S, TT <: AbstractTensorMap{E, S, 2, 2}} <: TNRScheme{E, S}
+    "Pure tensor"
     T::TT
+
+    "Impurity tensor on lattice site 1"
     T_imp1::TT
+
+    "Impurity tensor on lattice site 2"
     T_imp2::TT
+
+    "Impurity tensor on lattice site 3"
     T_imp3::TT
+
+    "Impurity tensor on lattice site 4"
     T_imp4::TT
 
     function ImpurityTRG(T::TT, T_imp1::TT, T_imp2::TT, T_imp3::TT, T_imp4::TT) where {E, S, TT <: AbstractTensorMap{E, S, 2, 2}}
         @assert space(T, 1) == space(T_imp1, 1) == space(T_imp2, 1) == space(T_imp3, 1) == space(T_imp4, 1) "First space of T, T_imp1, T_imp2, T_imp3 and T_imp4 must be the same"
         @assert space(T, 2) == space(T_imp1, 2) == space(T_imp2, 2) == space(T_imp3, 2) == space(T_imp4, 2) "Second space of T, T_imp1, T_imp2, T_imp3 and T_imp4 must be the same"
         @assert space(T, 3) == space(T_imp1, 3) == space(T_imp2, 3) == space(T_imp3, 3) == space(T_imp4, 3) "Third space of T, T_imp1, T_imp2, T_imp3 and T_imp4 must be the same"
         @assert space(T, 4) == space(T_imp1, 4) == space(T_imp2, 4) == space(T_imp3, 4) == space(T_imp4, 4) "Fourth space of T, T_imp1, T_imp2, T_imp3 and T_imp4 must be the same"
-
         return new{E, S, TT}(T, T_imp1, T_imp2, T_imp3, T_imp4)
     end
 end