Issue |
EPL
Volume 82, Number 6, June 2008
|
|
---|---|---|
Article Number | 60004 | |
Number of page(s) | 6 | |
Section | General | |
DOI | https://doi.org/10.1209/0295-5075/82/60004 | |
Published online | 30 May 2008 |
Pressure-induced quantum phase transitions
Department of Physics and Astronomy, University of Sheffield - Sheffield S3 7RH UK, EU
Corresponding author: g.gehring@shef.ac.uk
Received:
10
October
2007
Accepted:
30
April
2008
A quantum critical point is approached by applying pressure in a number of ferromagnetic and antiferromagnetic metals. The observed dependence of Tc on pressure necessarily means that the magnetic energy is coupled to the lattice. A first-order phase transition occurs if this coupling exceeds a critical value: this is inevitable if diverges as Tc approaches zero. It is argued that this is the cause of the first-order transition that is observed in many systems. Landau theory is used to obtain the phase diagram and also to predict the regions where metastable phases occur that agree well with experiments done on MnSi and other materials. The theory can be used to obtain very approximate values for the temperature and pressure at the tricritical point in terms of measured quantities. The values of the tricritical temperature for various materials obtained from Landau theory are too low but it is shown that the predicted values will rise if the effects of fluctuations are included.
PACS: 05.70.Fh – Phase transitions: general studies / 64.70.Tg – Quantum phase transitions / 75.20.En – Metals and alloys
© EPLA, 2008
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.