Thermo-electric charge-to-voltage converter with superconductor–insulator–normal tunnel junction for bolometer applications

A novel type of the zero-biased thermo-electric bolometer (TEB) is proposed. The bolometer is based on a charge-to-voltage converter (CVC) with a superconductor–insulator–normal (SIN) tunnel junction and a superconducting absorber. The absorption of photons in the absorber leads to excitation of quasiparticles with some fraction of charge imbalance, tunneling through the SIN junction in zero-biased mode and generation of voltage. The thermoelectric voltage is determined by accumulation of tunneling charge in an external capacitance. Conversion efficiency is very high and voltage values comparable with a superconducting gap are easily achieved. The zero-biased CVC–TEB can be effectively used for creation of an array of bolometers and multi-pixel detection systems.