RVB state, fractionalized S=1/2 spinons, gapless spectral continuum, Z₂ gauge structure
QSL: S=1 magnon → 2 × S=½ spinons; neutron scattering shows broad continuum (not sharp magnon peak)
RVB: |ψ⟩ = Σ amplitudes × |dimer coverings⟩; emergent Z₂ gauge field, vison excitations
In a quantum spin liquid, conventional magnetic order is frustrated away. The ground state is a superposition of resonating valence bond (RVB) configurations. Elementary excitations are fractionalized spinons (S=1/2, charge-neutral fermions) and bosonic visons (Z₂ flux). Kagome Heisenberg antiferromagnet and α-RuCl₃ (proximate Kitaev QSL) are leading candidates. Signature: diffuse spectral weight over extended (q,ω) region with lower edge ~2Δ_s.