In superconductors, the condensation of Cooper pairs gives rise to fluxoid quantization in discrete units of ${\mathrm{\Phi }}_0=hc/2e$. The denominator of $2e$ is the signature of electron pairing, which is evidenced by a number of macroscopic quantum phenomena, such as the Little-Parks effect and the Josephson effect, where the critical temperature or the critical current oscillates with the periodicity of ${\mathrm{\Phi }}_0$. Here we report the observation of Little-Parks oscillation periodicities of $2{\mathrm{\Phi }}_0$, $3{\mathrm{\Phi }}_0$, and $4{\mathrm{\Phi }}_0$, besides the conventional ${\mathrm{\Phi }}_0$, in mesoscopic rings of epitaxial $\beta -{\mathrm{Bi}}_2\mathrm{Pd}$, a topological superconductor. These unexpected findings suggest new physics to account for the observed quantizations.

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• Superconducting order parameter
• Superconducting phase transition
• Topological materials
• Vortices in superconductors
• Low-temperature superconductors
• Thin films
• Methods in superconductivity