Quantum Phase Transitions in Electronic Systems
Quantum phase transitions occur at zero temperature when some non-thermal control-parameter like pressure or chemical composition is changed. They are driven by quantum rather than thermal fluctuations. In this review we first give a pedagogical introduction to quantum phase transitions and quantum critical behavior emphasizing similarities with and differences to classical thermal phase transitions. We then illustrate the general concepts by discussing a few examples of quantum phase transitions occurring in electronic systems. The ferromagnetic transition of itinerant electrons shows a very rich behavior since the magnetization couples to additional electronic soft modes which generates an effective long-range interaction between the spin fluctuations. We then consider the influence of rare regions on quantum phase transitions in systems with quenched disorder, taking the antiferromagnetic transitions of itinerant electrons as a primary example. Finally we discuss some aspects of the metal-insulator transition in the presence of quenched disorder and interactions.
T. Vojta, "Quantum Phase Transitions in Electronic Systems," Annalen der Physik (Leipzig), vol. 9, no. 6, pp. 403-440, Wiley-VCH Verlag Berlin GmbH, Jun 2000.
The definitive version is available at http://dx.doi.org/10.1002/1521-3889(200006)9:6<403::AID-ANDP403>3.0.CO;2-R
Keywords and Phrases
Antiferromagnetism; Electron transitions; Ferromagnetism; Magnetic materials; Magnetization; Phase transitions; Itinerant magnets; Metal-insulator transition; Quantum phase transition; Quantum electronics
International Standard Serial Number (ISSN)
Article - Journal
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