Motivated by this question, I was wondering if there is a way to produce curved arrow heads with either pstricks and/or tikZ (alphabetic ordering;-). To be more specific, I'm interested in something like the top arrow in
which I produced with the feynmf code
\begin{fmfgraph*}(30,22)
\fmfleft{i}
\fmfright{o}
\fmf{fermion,label={}}{i,v,v,o}
\end{fmfgraph*}
(I only include the diagram code here because there are different ways of embedding these diagrams in LaTeX documents and please don't worry about the label={}. The way this curved arrow is produced is not relevant to the question, anyway.)


I detected a fmfgraph environment outside of fmffile. Do you know how to solve it? – Phelype Oleinik Jan 11 '18 at 17:40\begin{document} \begin{fmffile}{Test}and\end{fmffile} \end{document}in a document that loads\usepackage{feynmp}. And of course I run mpost. – Jan 11 '18 at 17:43:). In this case, I suggest you take a look at page 33 of the VisualTikZ. Also, try this:\documentclass{article} \usepackage{tikz} \usetikzlibrary{bending,arrows.meta} \begin{document} \tikz\draw[-{Stealth[length=1cm,open,bend]}] (0,0) .. controls (1,-1) and (2,1) .. (3,1); \end{document}. If you like, I make it an answer. – Phelype Oleinik Jan 11 '18 at 17:49