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Register a new userQuantum Magnets under Pressure: Controlling Elementary Excitations in TlCuCl3
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Added by
Christian R\\\"uegg
Publication date
2008
fields
Physics
and research's language is
English
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We follow the evolution of the elementary excitations of the quantum antiferromagnet TlCuCl3 through the pressure-induced quantum critical point, which separates a dimer-based quantum disordered phase from a phase of long-ranged magnetic order. We demonstrate by neutron spectroscopy the continuous emergence in the weakly ordered state of a low-lying but massive excitation corresponding to longitudinal fluctuations of the magnetic moment. This mode is not present in a classical description of ordered magnets, but is a direct consequence of the quantum critical point.
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