Pressure and magnetic field effects in heavy-fermion UCu$_{3.5}$Al$_{1.5 }$

UCu$_{3.5}$Al$_{1.5}$ crystallizes in the hexagonal CaCu$_{5}$ structure and is described as a heavy fermion, which shows non-Fermi liquid behavior[1]. Here, we report on electrical resistivity, magnetic susceptibility, and magnetization results on polycrystalline UCu$_{3.5}$Al$_{1.5}$. The resistivity was measured under hydrostatic pressure up to 10kbar and in fields up to 18T. At ambient pressure and in zero field, the resistivity shows an anomaly at T$_{1}$=19K and then it goes through a maximum at T$_{max}$=2K. These two anomalies were also observed in the susceptibility data. The anomaly in the resistivity at T$_{1}$ goes to lower values with increasing fields and disappear at fields about 12T. T$_{max}$ on the other hand goes to higher values with increasing fields. We find relatively weak pressure dependence, where both T$_{1}$ and T$_{max}$ go down with increasing pressure. In the field scan at 2K and at ambient pressure, we find a change in the slope of the magnetoresistance at about 6.9T. Application of pressure causes a reduction of the magnetoresistance effect. \newline [1] H. Nakotte, et al., Phys. Rev. B 54, 12176 (1996)