Jammed Spin Liquid in the Bond-Disordered Kagome Heisenberg Antiferromagnet*

We study a class of disordered continuous classical spin systems including the kagome Heisenberg magnet. While each term in its local Hamiltonian can be independently minimised, we find discrete degenerate ground states whose number grows exponentially with system size. These states do not exhibit zero-energy `excitations' characteristic of highly frustrated magnets but instead are local minima of the energy landscape, albeit with an anomalously soft excitation spectrum. This represents a spin liquid version of the phenomenon of jamming familiar from granular media and structural glasses. Correlations of this jammed spin liquid, which upon increasing the disorder strength gives way to a conventional spin glass, may be algebraic (Coulomb-type) or exponential.