Universal behavior at weak first order quantum phase transitions

✍ Scribed by Mucio A. Continentino; Andre S. Ferreira

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 107 KB
• Volume: 378-380
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2006.01.332

✦ Synopsis

First order quantum phase transitions besides their general interest are clearly relevant to the study of heavy fermions and magnetic transition metal compounds. Recent results show that in many systems belonging to these classes of materials, the magnetic transition changes from second order to first order as the quantum critical point (QCP) is approached. We are interested here in the case the change in the nature of the T ¼ 0 transition is due to a coupling of the order parameter to soft modes or to the competition between different types of order near the QCP. For these weak first order quantum phase transitions general results are obtained. In particular, we describe the thermodynamic behavior when this transition is approached from finite temperatures. This is the discontinuous equivalent of the non-Fermi liquid trajectory close to a conventional QCP, for example, in heavy fermion systems.