A quantum critical point


This figure summarises one of the key ideas associated with quantum phase transitions: a quantum critical region.
Diagrams such as this appear in many papers (particularly theory ones) but unless I am mistaken there is an actual paucity of real materials for which there is clear unambiguous evidence for actual quantum critical behaviour (i.e. no quasi-particles and only a single energy scale, k_B T).

I welcome readers posting their best examples.

Comments

  1. UnknownApril 6, 2010 at 6:26 AM

    you might enjoy this talk

    http://online.kitp.ucsb.edu/online/adscmt_m09/sondhi/

    because Prof.Sondhi points out some of the finer points of said diagram, both the implicit cutoff and the other effects...

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