Scanning electron microscopy image of a typical Nb multi-contact nanostrip configuration. The length of the studied segments amounts to 3 . The superconducting leads enable electrical transport measurements. This is illustrated for the third nanostrip of the top configuration. The current bias is applied using the contacts referred by the and symbols, while the nearest contacts on each side are used to measure the resulting voltage ( and symbols).
(Color online) (a) Overall current-driven behavior of the Nb nanostrip under an increasing microwave power ( = 6 K, 11.3 GHz). The input power varies from 0 mW to 6.3 mW. (b)-(c): Evolution of the normal-to-superconducting transition of the Nb nanostrip under an increasing microwave power ( = 6 K). The microwave frequency is 11.3 GHz and 8.9 GHz, respectively. The microwave input powers are indicated in mW.
(Color online) Evolution of the normal-to-superconducting transition of the NbN nanostrip under an increasing microwave power. The microwave frequency is 7 GHz and the coolant temperature is = 7 K. The microwave input powers are indicated in mW.
Evolution of the heat removal capabilities with respect to the difference between the critical temperature and the coolant temperature. The data are depicted for the Nb () and the NbN (□) samples.
(Color online) Evolution of the microwave power density absorbed in the normal state with respect to the input power . The data are depicted for the Nb nanostrip at three coolant temperatures = 8 K (, (a)), 6 K (, (b)), and 1.5 K (▪, (c)) and for the NbN (□) nanostrip at = 7 K (d). For Nb, the microwave frequencies are 8.9 GHz and 11.3 GHz, except at = 8 K, where the data are also displayed at 6.6 GHz. For NbN, the microwave frequency is 7 GHz. The dashed horizontal lines mark the heat evacuation capabilities level at the studied coolant temperatures, i.e., . The errors bars take into account that the local sample width used in Eq. (3) may differ from the nominal one by 5 nm.
(Color online) Independence of the absorbed microwave power density with respect to the coolant temperatures, i.e., = 1.5 K (▪), 6 K (), and 8 K () (Nb sample, frequency: 8.9 GHz (top) and 11.3 GHz (bottom)).
Article metrics loading...
Full text loading...