Add istrivial and istopological

Author: lkdvos

src/algorithms/excitation/exci_transfer_system.jl

@@ -6,6 +6,11 @@ function left_excitation_transfer_system(
     found = zerovector(GBL)
     odim = length(GBL)
 
+    if istrivial(exci)
+        ρ_left = l_RL(exci.right_gs)
+        ρ_right = r_RL(exci.right_gs)
+    end
+
     for i in 1:odim
         # this operation can in principle be even further optimized for larger unit cells
         # as we only require the terms that end at level i.
@@ -14,9 +19,7 @@ function left_excitation_transfer_system(
         H_partial = map(h -> getindex(h, 1:i, 1, 1, 1:i), parent(H))
         T = TransferMatrix(exci.right_gs.AR, H_partial, exci.left_gs.AL)
         start = scale!(last(found[1:i] * T), cis(-mom * len))
-        if exci.trivial && isidentitylevel(H, i)
-            ρ_left = l_RL(exci.right_gs)
-            ρ_right = r_RL(exci.right_gs)
+        if istrivial(exci) && isidentitylevel(H, i)
             regularize!(start, ρ_right, ρ_left)
         end
 
@@ -25,8 +28,8 @@ function left_excitation_transfer_system(
         if !isemptylevel(H, i)
             if isidentitylevel(H, i)
                 T = TransferMatrix(exci.right_gs.AR, exci.left_gs.AL)
-                if exci.trivial
-                    T = regularize(T, l_RL(exci.right_gs), r_RL(exci.right_gs))
+                if istrivial(exci)
+                    T = regularize(T, ρ_left, ρ_right)
                 end
             else
                 T = TransferMatrix(
@@ -53,6 +56,11 @@ function right_excitation_transfer_system(
     found = zerovector(GBR)
     odim = length(GBR)
 
+    if istrivial(exci)
+        ρ_left = l_LR(exci.right_gs)
+        ρ_right = r_LR(exci.right_gs)
+    end
+
     for i in odim:-1:1
         # this operation can in principle be even further optimized for larger unit cells
         # as we only require the terms that end at level i.
@@ -61,9 +69,7 @@ function right_excitation_transfer_system(
         H_partial = map(h -> h[i:end, 1, 1, i:end], parent(H))
         T = TransferMatrix(exci.left_gs.AL, H_partial, exci.right_gs.AR)
         start = scale!(first(T * found[i:odim]), cis(mom * len))
-        if exci.trivial && isidentitylevel(H, i)
-            ρ_left = l_LR(exci.right_gs)
-            ρ_right = r_LR(exci.right_gs)
+        if istrivial(exci) && isidentitylevel(H, i)
             regularize!(start, ρ_left, ρ_right)
         end
 
@@ -72,8 +78,8 @@ function right_excitation_transfer_system(
         if !isemptylevel(H, i)
             if isidentitylevel(H, i)
                 tm = TransferMatrix(exci.left_gs.AL, exci.right_gs.AR)
-                if exci.trivial
-                    tm = regularize(tm, l_LR(exci.left_gs), r_LR(exci.right_gs))
+                if istrivial(exci)
+                    tm = regularize(tm, ρ_left, ρ_right)
                 end
             else
                 tm = TransferMatrix(
@@ -82,8 +88,7 @@ function right_excitation_transfer_system(
             end
 
             found[i], convhist = linsolve(
-                tm, found[i], found[i], solver, 1,
-                -cis(mom * len)
+                tm, found[i], found[i], solver, 1, -cis(mom * len)
             )
             convhist.converged < 1 &&
                 @warn "GBR$i failed to converge: normres = $(convhist.normres)"

src/algorithms/excitation/quasiparticleexcitation.jl

@@ -57,7 +57,7 @@ function excitations(H, alg::QuasiparticleAnsatz, ϕ₀::InfiniteQP, lenvs, renv
 end
 function excitations(H, alg::QuasiparticleAnsatz, ϕ₀::InfiniteQP, lenvs; num = 1, kwargs...)
     # Infer `renvs` in function body as it depends on `solver`.
-    renvs = ϕ₀.trivial ? lenvs : environments(ϕ₀.right_gs, H; kwargs...)
+    renvs = !istopological(ϕ₀) ? lenvs : environments(ϕ₀.right_gs, H; kwargs...)
     return excitations(H, alg, ϕ₀, lenvs, renvs; num, kwargs...)
 end
 function excitations(H, alg::QuasiparticleAnsatz, ϕ₀::InfiniteQP; num = 1, kwargs...)
@@ -136,7 +136,7 @@ end
 function excitations(
         H, alg::QuasiparticleAnsatz, ϕ₀::FiniteQP,
         lenvs = environments(ϕ₀.left_gs, H),
-        renvs = ϕ₀.trivial ? lenvs : environments(ϕ₀.right_gs, H);
+        renvs = !istopological(ϕ₀) ? lenvs : environments(ϕ₀.right_gs, H);
         num = 1
     )
     E = effective_excitation_renormalization_energy(H, ϕ₀, lenvs, renvs)
@@ -223,7 +223,7 @@ function excitations(
         kwargs...
     )
     # Infer `renvs` in function body as it depends on `solver`.
-    renvs = ϕ₀.trivial ? lenvs : environments(ϕ₀.right_gs, H; kwargs...)
+    renvs = !istopological(ϕ₀) ? lenvs : environments(ϕ₀.right_gs, H; kwargs...)
     return excitations(H, alg, ϕ₀, lenvs, renvs; kwargs...)
 end
 function excitations(
@@ -372,7 +372,7 @@ function effective_excitation_renormalization_energy(H, ϕ, lenvs, renvs)
         E[i] = contract_mpo_expval(
             ψ_left.AC[i], leftenv(lenvs, i, ψ_left), H[i], rightenv(lenvs, i, ψ_left)
         )
-        if !ϕ.trivial
+        if istopological(ϕ)
             E[i] += contract_mpo_expval(
                 ψ_right.AC[i], leftenv(renvs, i, ψ_right), H[i], rightenv(renvs, i, ψ_right)
             )

src/algorithms/toolbox.jl

@@ -225,7 +225,7 @@ end
 
 function variance(state::InfiniteQP, H::InfiniteMPOHamiltonian, envs = environments(state, H))
     # I remember there being an issue here @gertian?
-    state.trivial ||
+    istopological(state) &&
         throw(ArgumentError("variance of domain wall excitations is not implemented"))
     gs = state.left_gs
 

src/environments/qp_envs.jl

@@ -33,7 +33,7 @@ function environments(exci::Union{InfiniteQP, MultilineQP}, H; kwargs...)
     return environments(exci, H, lenvs; kwargs...)
 end
 function environments(exci::Union{InfiniteQP, MultilineQP}, H, lenvs; kwargs...)
-    renvs = exci.trivial ? lenvs : environments(exci.right_gs, H; kwargs...)
+    renvs = !istopological(exci) ? lenvs : environments(exci.right_gs, H; kwargs...)
     return environments(exci, H, lenvs, renvs; kwargs...)
 end
 
@@ -62,7 +62,7 @@ function environments(exci::InfiniteQP, H::InfiniteMPOHamiltonian, lenvs, renvs;
         lBs[pos + 1] += leftenv(lenvs, pos, exci.left_gs) *
             TransferMatrix(exci[pos], H[pos], AL[pos]) / cis(exci.momentum)
 
-        if exci.trivial && !isempty(ids) # regularization of trivial excitations
+        if istrivial(exci) && !isempty(ids) # regularization of trivial excitations
             ρ_left = l_RL(exci.left_gs, pos + 1)
             ρ_right = r_RL(exci.left_gs, pos)
             for i in ids
@@ -78,7 +78,7 @@ function environments(exci::InfiniteQP, H::InfiniteMPOHamiltonian, lenvs, renvs;
         rBs[pos - 1] += TransferMatrix(exci[pos], H[pos], AR[pos]) *
             rightenv(renvs, pos, exci.right_gs) * cis(exci.momentum)
 
-        if exci.trivial && !isempty(ids)
+        if istrivial(exci) && !isempty(ids)
             ρ_left = l_LR(exci.left_gs, pos)
             ρ_right = r_LR(exci.left_gs, pos - 1)
             for i in ids
@@ -100,7 +100,7 @@ function environments(exci::InfiniteQP, H::InfiniteMPOHamiltonian, lenvs, renvs;
     for i in 1:(length(exci) - 1)
         lB_cur = lB_cur * TransferMatrix(AR[i], H[i], AL[i]) / cis(exci.momentum)
 
-        if exci.trivial && !isempty(ids)
+        if istrivial(exci) && !isempty(ids)
             ρ_left = l_RL(exci.left_gs, i + 1)
             ρ_right = r_RL(exci.left_gs, i)
             for k in ids
@@ -115,7 +115,7 @@ function environments(exci::InfiniteQP, H::InfiniteMPOHamiltonian, lenvs, renvs;
     for i in length(exci):-1:2
         rB_cur = TransferMatrix(AL[i], H[i], AR[i]) * rB_cur * cis(exci.momentum)
 
-        if exci.trivial && !isempty(ids)
+        if istrivial(exci) && !isempty(ids)
             ρ_left = l_LR(exci.left_gs, i)
             ρ_right = r_LR(exci.left_gs, i - 1)
             for k in ids
@@ -132,7 +132,7 @@ end
 function environments(
         exci::FiniteQP, H::FiniteMPOHamiltonian,
         lenvs = environments(exci.left_gs, H),
-        renvs = exci.trivial ? lenvs : environments(exci.right_gs, H);
+        renvs = !istopological(exci) ? lenvs : environments(exci.right_gs, H);
         kwargs...
     )
     AL = exci.left_gs.AL
@@ -161,7 +161,7 @@ function environments(
 end
 
 function environments(exci::InfiniteQP, O::InfiniteMPO, lenvs, renvs; kwargs...)
-    exci.trivial ||
+    istopological(exci) &&
         @warn "there is a phase ambiguity in topologically nontrivial statmech excitations"
     solver = environment_alg(exci, O, exci; kwargs...)
 
@@ -203,7 +203,7 @@ function environments(exci::InfiniteQP, O::InfiniteMPO, lenvs, renvs; kwargs...)
     T_RL = TransferMatrix(right_gs.AR, O, left_gs.AL)
     T_LR = TransferMatrix(left_gs.AL, O, right_gs.AR)
 
-    if exci.trivial
+    if istrivial(exci)
         @plansor rvec[-1 -2; -3] := rightenv(lenvs, 0, left_gs)[-1 -2; 1] *
             conj(left_gs.C[0][-3; 1])
         @plansor lvec[-1 -2; -3] := leftenv(lenvs, 1, left_gs)[-1 -2; 1] *

src/states/quasiparticle_state.jl

@@ -133,7 +133,7 @@ function Base.convert(
 
     tm = TransferMatrix(input.left_gs.AL, input.right_gs.AR)
 
-    if input.trivial
+    if istrivial(input)
         tm = regularize(tm, l_LR(input.right_gs), r_LR(input.right_gs))
     end
 
@@ -180,7 +180,7 @@ function Base.convert(
     end
 
     tm = TransferMatrix(input.right_gs.AR, input.left_gs.AL)
-    if input.trivial
+    if istrivial(input)
         tm = regularize(tm, l_RL(input.right_gs), r_RL(input.right_gs))
     end
 
@@ -222,9 +222,12 @@ left_virtualspace(state::QP) = map(Base.Fix1(left_virtualspace, state), eachsite
 right_virtualspace(state::QP, i::Int) = right_virtualspace(state.right_gs, i)
 right_virtualspace(state::QP) = map(Base.Fix1(right_virtualspace, state), eachsite(state))
 auxiliaryspace(state::QP) = space(state.Xs[1], 2)
-
+auxiliarysector(state::QP) = only(sectors(auxiliaryspace(state)))
 eachsite(state::QP) = eachsite(state.left_gs)
 
+istopological(qp::QP) = qp.left_gs !== qp.right_gs
+istrivial(qp::QP) = !istopological(qp) && isone(auxiliarysector(qp))
+
 Base.copy(a::QP) = copy!(similar(a), a)
 Base.copyto!(a::QP, b::QP) = copy!(a, b)
 function Base.copy!(a::T, b::T) where {T <: QP}
@@ -233,11 +236,12 @@ function Base.copy!(a::T, b::T) where {T <: QP}
     end
     return a
 end
-function Base.getproperty(v::QP, s::Symbol)
+Base.@constprop :aggressive function Base.getproperty(qp::QP, s::Symbol)
     if s == :trivial
-        return v.left_gs === v.right_gs
+        Base.depwarn("`qp.trivial` is deprecated in favor of `istrivial` and `istopological`", :trivial)
+        return !istopological(qp)
     else
-        return getfield(v, s)
+        return getfield(qp, s)
     end
 end
 
@@ -402,7 +406,7 @@ function Base.convert(::Type{<:FiniteMPS}, v::QP{S}) where {S <: FiniteMPS}
     return FiniteMPS(Ls + Rs + Bs; normalize = false)
 end
 
-function Base.getproperty(exci::MultilineQP, s::Symbol)
+Base.@constprop :aggressive function Base.getproperty(exci::MultilineQP, s::Symbol)
     if s == :momentum
         return first(exci.data).momentum
     elseif s == :left_gs
@@ -416,6 +420,10 @@ function Base.getproperty(exci::MultilineQP, s::Symbol)
     end
 end
 
+# These should really all be the same, so it might make sense to take the first instead
+istrivial(exci::MultilineQP) = all(istrivial, exci.data)
+istopological(exci::MultilineQP) = all(istopological, exci.data)
+
 # VectorInterface
 # ---------------