Edit and compile if you like:
\documentclass[tikz]{standalone}\begin{document}\begin{tikzpicture}[thick]% Dot grid\def\xrange{3}\def\yrange{3}\def\ratio{3/4}\foreach \x in {-\xrange,...,\xrange}{\foreach \y in {-\yrange,...,\yrange}{\fill (\x,\ratio*\y) circle[radius=2pt];}}% Axes\draw[->] (-\xrange-1/2,0) -- (\xrange+1/2,0) node[above left] {$k_x$};\draw[->] (0,-\ratio*\yrange-1/2) -- (0,\ratio*\yrange+1/2) node[below right] {$k_y$};% Lattice spacing\draw[<->,shorten >=3,shorten <=3] (\xrange-1,-\ratio*\yrange) -- (\xrange,-\ratio*\yrange) node[midway,below] {$\frac{2 \pi}{L_x}$};\draw[<->,shorten >=3,shorten <=3] (\xrange,-\ratio*\yrange) -- (\xrange,-\ratio*\yrange+\ratio) node[midway,right] {$\frac{2 \pi}{L_y}$};% Circle\draw[blue,fill=blue,fill opacity=0.1] (0,0) circle (2/3*\yrange);\node[blue] at (130:2.4) {$N(k)$};\end{tikzpicture}\end{document}
Click to download: k-space.tex
Open in Overleaf: k-space.tex
This file is available on tikz.netlify.app and on GitHub and is MIT licensed.
See more on the author page of Janosh Riebesell..