The ground state of a quantum critical system

Wouter Montfrooij; Jagat Lamsal; Meigan Aronson; Marcus Bennett; Anne de Visser; Huang Ying Kai; Nguyen Thanh Huy; Mohana Yethiraj; Mark Lumsden; Yiming Qiu

arXiv · cond-mat/0606703

The ground state of a quantum critical system

Wouter Montfrooij·Jagat Lamsal·Meigan Aronson·Marcus Bennett·Anne de Visser·Huang Ying Kai·Nguyen Thanh Huy·Mohana Yethiraj·Mark Lumsden·Yiming Qiu

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Abstract

The competition between the tendency of magnetic moments to order at low temperatures, and the tendency of conduction electrons to shield these moments, can result in a phase transition that takes place at zero Kelvin, the quantum critical point (QCP). So far, the ground state of these types of systems has remained unresolved. We present neutron scattering experiments that show that the ground state of a sample representative of a class of QCP-systems is determined by the residual interactions between the conduction electrons, resulting in a state with incommensurate intermediate-range order. However, long-range order is thwarted by quantum fluctuations that locally destroy magnetic moments, leaving the system with too few moments to achieve long-range order.

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Wouter Montfrooij, Jagat Lamsal, Meigan Aronson, Marcus Bennett, Anne de Visser, Huang Ying Kai, Nguyen Thanh Huy, Mohana Yethiraj, Mark Lumsden, Yiming Qiu. 2006-06-27. The ground state of a quantum critical system. https://arxiv.org/abs/cond-mat/0606703

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