Josephson junction infrared single-photon detector

Abstract

Josephson junctions are superconducting devices used as high-sensitivity magnetometers and voltage amplifiers as well as the basis of high-performance cryogenic computers and superconducting quantum computers. Although device performance can be degraded by the generation of quasiparticles formed from broken Cooper pairs, this phenomenon also opens opportunities to sensitively detect electromagnetic radiation. We demonstrate single near-infrared photon detection by coupling photons to the localized surface plasmons of a graphene-based Josephson junction. Using the photon-induced switching statistics of the current-biased device, we reveal the critical role of quasiparticles generated by the absorbed photon in the detection mechanism. The photon sensitivity will enable a high-speed, low-power optical interconnect for future superconducting computing architectures.

Out-of-equilibrium phonons in gated superconducting switches

“…Previous works detected photons in a variety of devices as a result of tunnelling events 39 – 43 as well as bremsstrahlung and carrier recombination of high-energy electrons 44 , 45 . It is also well known that superconducting nanowires 46 and Josephson junctions 47 are highly sensitive to the impact of high-energy photons. Both phonon and photon transport may be affected by the additional fabrication steps for trenching, for example, by a change in surface roughness or dielectric properties.…”

Evidence of Josephson Coupling in a Few-Layer Black Phosphorus Planar Josephson Junction

“…Among all, bP devices are exploited as widely tunable infrared photodetectors, 78 − 80 and optimized bP-based planar Josephson junctions are thus a promising platform for infrared single-photon detectors. 4 , 81 …”

“…To start with, such devices offer the great opportunity to study fundamental aspects of distinct physics, such as Dirac-like relativistic behavior in combination with superconductivity, 34 − 37 and are a promising platform for advanced sensing and detection down to the single photon in a wide spectral range. 4 Importantly, the superconducting contacts can be placed laterally, retaining the surface of the device free, allowing for the spatially resolved investigation of correlations and transport properties, providing also the possibility to add top gates. This has triggered great experimental efforts to realize hybrid JJs with 2D flakes and led in 2007 to the fabrication and characterization of a graphene-based JJ device, 34 demonstrating a bipolar tuning of supercurrent amplitude with well-developed Josephson coupling.…”

Nanomaterials for Quantum Information Science and Engineering

“…Atomically thin superconductors will have a lower heat capacity than the bulk and therefore could be more sensitive to single photons [561] . Recently, Walsh et al utilized the localized surface plasmon modes of graphene to couple light to a graphene-based JJ [574] . Incident single photons couple to plasmons in the graphene and break Cooper pairs in the superconductor, forming quasiparticles that, in turn, induce a diffusion current across the junction, enabled by quasiballistic transport through graphene.…”