ISSN:
1077-3118
Source:
AIP Digital Archive
Topics:
Physics
Notes:
A new model is proposed in which a photon of energy E=hf is absorbed by a superconducting film to create a pair of equal and opposite fluxons (or vortices), each with quantized flux Φ0=h/2e. An applied current sweeps these fluxons to opposite edges of the film, causing a voltage pulse with time-integrated magnitude Φ0, and leading to a time-averaged voltage responsivity Rv = Φ0/E = 1/(2ef). This is directly analogous to photoconductive detection in a semiconductor via creation of electron-hole pairs. Data on an ultrathin granular NbN film are presented which indicate a responsivity of 6000 V/W in red light, in agreement with the model. This is promising for the development of a sensitive, high-speed infrared detector using thin films of either low or high Tc superconductors.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.103760
