Fermi surface reconstruction and dimensional topology change in Nd-doped ${\mathrm{CeCoIn}}_5$

We performed low-temperature de Haas–van Alphen effect measurements on a ${\mathrm{Ce}}_{1-x}{\mathrm{Nd}}_x{\mathrm{CoIn}}_5$ series, for $x=0.02$, 0.05, 0.1, and 1, down to $T=40$ mK using torque magnetometry in magnetic fields up to 35 T. Our results indicate that a Fermi surface (FS) reconstruction occurs from a quasi-two-dimensional topology for $\mathrm{Nd}\text{−}2\%$ to a rather three-dimensional one for $\mathrm{Nd}\text{−}5\%$, thus reducing the possibility of perfect FS nesting. The FS evolves further with increasing Nd content with no observed divergence of the effective mass between $\mathrm{Nd}\text{−}2\%$ and $10\%$, consistent with the crossing of a spin density wave type of quantum critical point. Our results elucidate the origin of the $Q$ phase observed at the $5\%$ Nd-doping level [Raymond et al., J. Phys. Soc. Jpn. 83, 013707 (2014)].

Figure 1

Fourier transform of the quantum oscillations between 21 and 35 T measured on ${\mathrm{NdCoIn}}_5$ at an angle $\theta =2^{\circ }$ from [001] to [110]. The inset shows the torque signal at high magnetic fields after background subtraction.

Figure 2

Angular dependence of the dHvA frequencies for (a) $\mathrm{Nd}\text{−}2\%$, (b) $5\%$, (c) $10\%$, and (d) $100\%$. The latter includes the results of the band-structure calculations, shown as lines. The labeling of the frequency branches has been defined so as to be consistent with prior works [27, 30]. Dashed lines denote $1/cos\theta$ dependence arising from a 2D cylindrical FS, dotted from a 3D sphere. The inset in (c) depicts the fast Fourier transform (FFT) for $\theta =7.2^{\circ }$.

Figure 3

Calculated FSs for ${\mathrm{NdCoIn}}_5$ (left) and ${\mathrm{CeCoIn}}_5$ (right). The black frames depict the first Brillouin zone. The solid lines on the FSs aid in the visualization of some extremal orbits for the magnetic field aligned along the $c$ axis. For ${\mathrm{NdCoIn}}_5$ (left), 66 is a hole band while 67 and 68 are electron bands.

Figure 4

Example of the temperature dependence of the observed frequencies in ${\mathrm{NdCoIn}}_5$ measured between 21 and 35 T at an angle of $\theta ={10}^{\circ }$ from [001] to [110].