We propose a single-photon detector based on a superconducting quantum interference device (SQUID) with superconductor-normal-metal-superconductor Josephson weak links. One of the two Josephson junctions is connected to an antenna, and is heated when a photon is absorbed. The increase of the weak-link temperature exponentially suppresses the Josephson critical current, thereby inducing an asymmetry in the SQUID. This generates a voltage pulse across the SQUID that can be measured with a threshold detector. Realized with realistic parameters, the device can be used as a single-photon detector - and as a calorimeter, since it is able to discriminate photon frequencies above 5THz with a signal-to-noise ratio larger than 20. The performance of the detector is robust with respect to working temperatures between 0.1 and 0.5K, and with respect to thermal noise perturbation.
Proximity SQUID Single-Photon Detector via Temperature-to-Voltage Conversion
Solinas P;Giazotto F;Pepe GP
2018
Abstract
We propose a single-photon detector based on a superconducting quantum interference device (SQUID) with superconductor-normal-metal-superconductor Josephson weak links. One of the two Josephson junctions is connected to an antenna, and is heated when a photon is absorbed. The increase of the weak-link temperature exponentially suppresses the Josephson critical current, thereby inducing an asymmetry in the SQUID. This generates a voltage pulse across the SQUID that can be measured with a threshold detector. Realized with realistic parameters, the device can be used as a single-photon detector - and as a calorimeter, since it is able to discriminate photon frequencies above 5THz with a signal-to-noise ratio larger than 20. The performance of the detector is robust with respect to working temperatures between 0.1 and 0.5K, and with respect to thermal noise perturbation.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
