The quantum functional intermetallic compound Pr_1-x-yLa_xPb_yTe

The intermetallic compound Pr_1-x-yLa_xPb_yTe shows a wide spectrum of physical phenomena*. Depending on the metallurgical composition as function of x and y, the compound changes its behaviour from nuclear magnetic order to super- or semiconductivity. In addition, there are interesting interplay effects between these ground state phenomena. In consequence, Pr_1-x-yLa_xPb_yTe may serve as an interesting candidate for studies on quantum computing. In this talk, experimental results taken in a wide range of temperature, 0.1 mK ≤ T ≤ 300 K, are presented. Further, effects which arise through the application of high magnetic fields are discussed.

* Whereas several rare earth tellurides undergo magnetic order, in PrTe the crystal electrical field splitting with a singlet ground state leads to Van Vleck paramagnetism. However, the nuclear magnetic moments of Pr are hyperfine enhanced as well as strongly coupled to the conduction electrons in PrTe. In consequence the effective nuclear magnetic moments order antiferromagnetically at 0.6 mK. LaTe is a superconductor with T_c = 5.7 K. The singlet ground state of the Pr ions in Pr_1-xLa_xTe lead to a large critical Pr concentration x = 0.5 for Cooper pair breaking. Finally, PbTe is a narrow band semiconductor.