diff --git a/src/operators/mpohamiltonian.jl b/src/operators/mpohamiltonian.jl
index 97f938609..2b3a6d518 100644
--- a/src/operators/mpohamiltonian.jl
+++ b/src/operators/mpohamiltonian.jl
@@ -43,7 +43,7 @@ function FiniteMPOHamiltonian(Ws::AbstractVector{O}) where {O <: MPOTensor}
     return FiniteMPOHamiltonian{O}(Ws)
 end
 
-const InfiniteMPOHamiltonian{O <: MPOTensor} = MPOHamiltonian{O, PeriodicVector{O}}
+const InfiniteMPOHamiltonian{O <: MPOTensor} = MPOHamiltonian{O, <:PeriodicVector{O}}
 Base.isfinite(::Type{<:InfiniteMPOHamiltonian}) = false
 
 function InfiniteMPOHamiltonian(Ws::AbstractVector{O}) where {O <: MPOTensor}
diff --git a/src/utility/periodicarray.jl b/src/utility/periodicarray.jl
index 14ce75b65..867c714eb 100644
--- a/src/utility/periodicarray.jl
+++ b/src/utility/periodicarray.jl
@@ -26,11 +26,17 @@ A[-1, 1], A[1, 1], A[4, 5]
 
 See also [`PeriodicVector`](@ref), [`PeriodicMatrix`](@ref)
 """
-struct PeriodicArray{T, N} <: AbstractArray{T, N}
-    data::Array{T, N}
+struct PeriodicArray{T, N, A <: AbstractArray{T, N}} <: AbstractArray{T, N}
+    data::A
+    PeriodicArray{T,N}(data::A) where A <: AbstractArray{T,N} where {T,N} = new{T,N,A}(data)
+    PeriodicArray{T,N,A}(data::A) where A <: AbstractArray{T,N} where {T,N} = new{T,N,A}(data)
 end
-PeriodicArray(data::AbstractArray{T, N}) where {T, N} = PeriodicArray{T, N}(data)
-PeriodicArray{T}(data::AbstractArray{T, N}) where {T, N} = PeriodicArray{T, N}(data)
+PeriodicArray(data::AbstractArray{T,N}) where {T,N} = PeriodicArray{T,N}(data)
+PeriodicArray{T}(data::AbstractArray{T,N}) where {T,N} = PeriodicArray{T,N}(data)
+
+
+
+
 function PeriodicArray{T}(initializer, args...) where {T}
     return PeriodicArray(Array{T}(initializer, args...))
 end
@@ -88,15 +94,15 @@ end
 Base.BroadcastStyle(::Type{T}) where {T <: PeriodicArray} = Broadcast.ArrayStyle{T}()
 
 function Base.similar(
-        bc::Broadcast.Broadcasted{<:Broadcast.ArrayStyle{<:PeriodicArray}}, ::Type{T}
-    ) where {T}
-    return PeriodicArray(similar(Array{T}, axes(bc)))
+        bc::Broadcast.Broadcasted{Broadcast.ArrayStyle{PeriodicArray{T, N, A}}}, ::Type{ElType}
+    ) where {A <: AbstractArray{T, N}} where {T, N, ElType}
+    return PeriodicArray(similar(convert(Broadcast.Broadcasted{typeof(Broadcast.BroadcastStyle(A))}, bc), ElType))
 end
 
 # Conversion
 # ----------
-Base.convert(::Type{T}, A::AbstractArray) where {T <: PeriodicArray} = T(A)
+Base.convert(::Type{PeriodicArray}, A::AbstractArray) = PeriodicArray(A)
 Base.convert(::Type{T}, A::PeriodicArray) where {T <: AbstractArray} = convert(T, parent(A))
 # fix ambiguities
-Base.convert(::Type{T}, A::PeriodicArray) where {T <: PeriodicArray} = A
-Base.convert(::Type{T}, A::PeriodicArray) where {T <: Array} = parent(A)
+Base.convert(::Type{PeriodicArray}, A::PeriodicArray) = A
+Base.convert(::Type{T}, A::PeriodicArray) where {T <: AbstractArray} = convert(T, parent(A))