Infinite series of magnetization plateaus in the frustrated dimer-plaquette chain

The dimer-plaquette chain undergoes a first-order transition driven by frustration to an orthogonal-dimer ground state. We analyze the magnetization curve in this orthogonal-dimer regime. Besides the recently found magnetization plateaus at $m=1/4$ and $m=1/2$ we find an infinite series of plateaus between $m=1/4$ and $m=1/2.$ These additional plateaus are connected by single jumps and belong to magnetizations $m(n)=n/(2n+2),$ where n is a positive integer number. The resulting magnetization curve looks like a staircase from $m=0$ to $m=1/2$ with steps decreasing rapidly in their width and height.