B-T phase diagram

Recently MAQO experiments have also been performed for the Kondo lattice compound CePbj, see Niki et al. (1987). Figure 43 shows relative velocity changes for the c - Cj2 mode for B k in the temperature range between 0.38 K to 1.7 K. For magnetic fields from 18-23 T a clear MAQO with frequency F = 617 T is observed with an effective mass m lm = 43. More extensive experiments have to be performed in order to determine the Fermi surface geometry. The complicated B-T phase diagram will be discussed in sect. 4. 

Obviously the B-T phase diagram of UPtj, the x-t diagram of Ui Th, .Bei3, see below, and the p-T diagram of He share striking similarities. This fact may, however, be fortuitous in view of the pronounced differences with respect to, e.g., symmetry and purity. 

Fig. 19. B-T phase diagram of CeCu2Si2 for B a. The original version of this phase diagram is from Bruls et al. (1994) while the completed version is from Weickert et al. (2004). For this sample the A-phase is expelled from the SC region (no coexistence).

Fig. 29. Superconducting B-T phase diagram as obtained from thermal expansion and magnetostriction (van Dijk et al., 1993 van Dijk, 1994). Critical field curves cross at a tetracritical point which is present for all field directions, therefore three distinct SC phases A(1,0), and C(0,1) with...

Fig. 48. B-T phase diagram of hidden order (HO) phase (I), metamagnetic phase (III) and high field phase (IV). Open symbols correspond to resistivity anomalies and filled symbols to specific heat maxima. For zero field Tq = 17.5 K (HO) (Jaime et al., 2002).

Fig. 63. Left panel Complete B-T phase diagram (Maple et al., 2002) with SC regime and region of field induced order parameter which is presumably of antiferroquadrupolar (AFQ) type. Data are obtained from resistivity (p), magnetization (M), specific heat (C) and thermal expansion (o ) measurements. Right panel High magnetic field phase diagram (Aoki et al., 2003) with upper part of AFQ phase (full squares) and line of high field Schottky anomaly from the Fi-Fs crossing. The inset shows calculation for tetrahedral CEF model.

The experiments on field-angle dependent thermal conductivity described in sect. 2 are a more powerful method to investigate the SC state. This method achieved the determination of critical field curves and the associated B-T phase diagram in PrOs4Sbi2 (Izawa et al., 2003) and at the same time the nodal structure of the gap function has at least been partly clarified. The same geometry as for borocarbides (sect. 5) with conical field rotation around the heat current... 

Fig. 66. B T phase diagram of PrOs4Sbi2 exhibiting B-phase with two-fold symmetry and A-phase with four-fold symmetry in a cubic plane. The A-phase and B-phase gap symmetries are indicated. They have four and two point nodes in a cubic plane, respectively (Izawa et al., 2003).

Figure E.7 (a) Magnetic phase diagram of type II superconductors (b) B-T phase diagram of...

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