Tantalum nitride superconducting single-photon detectors with low cut-off energy
Abstract
Materials with a small superconducting energy gap are expected to favor a high detection efficiency of low-energy photons in superconducting nanowire single-photon detectors. We developed a TaN detector with smaller gap and lower density of states at the Fermi energy than in comparable NbN devices, while other relevant parameters remain essentially unchanged. The observed reduction of the minimum photon energy required for direct detection is in line with model predictions of ≈1/3 as compared to NbN.
- Publication:
-
Applied Physics Letters
- Pub Date:
- February 2012
- DOI:
- 10.1063/1.3684243
- arXiv:
- arXiv:1110.4576
- Bibcode:
- 2012ApPhL.100f2601E
- Keywords:
-
- electronic density of states;
- Fermi level;
- nanowires;
- superconducting energy gap;
- superconducting materials;
- tantalum compounds;
- 74.25.Jb;
- 73.21.Hb;
- 73.20.At;
- 74.70.-b;
- Electronic structure;
- Quantum wires;
- Surface states band structure electron density of states;
- Superconducting materials;
- Condensed Matter - Superconductivity;
- Condensed Matter - Mesoscale and Nanoscale Physics
- E-Print:
- 9 pages incl. 1 table and 2 figures