2006/09/21 by Florian R. Ong, Florian Ong, Olivier Bourgeois +4
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Topological Materials and Phenomena #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.74.140503
To be published in Physical Review B, Rapid Communications
arxiv created 2006/09/21 · openalex publication_date 2006/10/13 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present measurements of thermal signatures of the Little-Parks effect using a highly sensitive nanocalorimeter. Small variations of the heat capacity Cp of 2.5 millions of noninteracting micrometer-sized superconducting rings threaded by a magnetic flux \ensuremathΦ have been measured by attojoule calorimetry. This noninvasive method allows the measurement of thermodynamic properties---and hence the probing of the energy levels---of nanosystems without perturbing them electrically. It is observed that Cp is strongly influenced by the fluxoid quantization (Little-Parks effect) near the critical temperature Tc. The jump of Cp at the superconducting phase transition is an oscillating function of \ensuremathΦ with a period \ensuremathΦ0=h∕2e, the magnetic flux quantum, which is in agreement with the Ginzburg-Landau theory of superconductivity.