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تسجيل مستخدم جديدQuantum-critical spin dynamics in a Tomonaga-Luttinger liquid studied with muon-spin relaxation
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We demonstrate that quantum-critical spin dynamics can be probed in high magnetic fields using muon-spin relaxation ($mu^{+}$SR). Our model system is the strong-leg spin ladder bis(2,3-dimethylpyridinium) tetrabromocuprate (DIMPY). In the gapless Tomonaga-Luttinger liquid phase we observe finite-temperature scaling of the $mu^{+}$SR $1/T_1$ relaxation rate which allows us to determine the Luttinger parameter $K$. We discuss the benefits and limitations of local probes compared with inelastic neutron scattering.
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