# Thermal expansion and magnetostriction close to quantum criticality

Tuesday 06 October 2009, 13:30

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Markus Garst, (University of Cologne)

Markus Garst - University of Cologne

Quantum phase transitions occur in materials at zero temperature upon tuning an external parameter, e.g., magnetic field to an instability of the ground state. A coupling of the quantum critical fluctuations to the lattice degrees of freedom can be exploited to probe quantum criticality at finite temperatures. The resulting anomalous signatures in thermal expansion, magnetostriction and the Gr\ā€¯uneisen parameter provide a valuable tool not only to detect but also to classify a quantum phase transition. As an example we discuss, in particular, the critical properties of the spin-ladder compound (C$_5$H$_{12}$N)$_2$CuBr$_4$, that exhibits a diverging thermal expansion.

Event type |
Seminar |

Start date and time |
Tuesday 06 October 2009, 13:30 |

End |
Tuesday 06 October 2009, 14:30 |

Location |
CR11, R3 |

Maximum Audience |
20 |