The electron-phonon relaxation time in thin superconducting titanium nitride films

A. Kardakova; M. Finkel; D. Morozov; V. Kovalyuk; P. An; C. Dunscombe; M. Tarkhov; P. Mauskopf; T. M. Klapwijk; G. Goltsman

doi:10.1063/1.4851235

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arXiv · 1312.5966

The electron-phonon relaxation time in thin superconducting titanium nitride films

A. Kardakova·M. Finkel·D. Morozov·V. Kovalyuk·P. An·C. Dunscombe·M. Tarkhov·P. Mauskopf·T. M. Klapwijk·G. Goltsman

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Abstract

We report on the direct measurement of the electron-phonon relaxation time, {\tau}eph, in disordered TiN films. Measured values of {\tau}eph are from 5.5 ns to 88 ns in the 4.2 to 1.7 K temperature range and consistent with a T-3 temperature dependence. The electronic density of states at the Fermi level N0 is estimated from measured material parameters. The presented results confirm that thin TiN films are promising candidate-materials for ultrasensitive superconducting detectors.

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A. Kardakova, M. Finkel, D. Morozov, V. Kovalyuk, P. An, C. Dunscombe, M. Tarkhov, P. Mauskopf, T. M. Klapwijk, G. Goltsman. 2013-12-20. The electron-phonon relaxation time in thin superconducting titanium nitride films. https://doi.org/10.1063/1.4851235

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