Unconventional Applications of Superconducting Nanowire Single Photon Detectors

Abstract

Superconducting nanowire single photon detectors are becoming a dominant technology in quantum optics and quantum communication, primarily because of their low timing jitter and capability to detect individual low-energy photons with high quantum efficiencies. However, other desirable characteristics, such as high detection rates, operation in cryogenic and high magnetic field environments, or high-efficiency detection of charged particles, are underrepresented in literature, potentially leading to a lack of interest in other fields that might benefit from this technology. We review the progress in use of superconducting nanowire technology in photon and particle detection outside of the usual areas of physics, with emphasis on the potential use in ongoing and future experiments in nuclear and high energy physics.

Keywords: nanowires; particle detectors; photon detectors; quantum detectors; superconductivity.

Figure 1

Schematic of the detection process through the hot spot formation after a photon absorption. Equilibrium superconductor is in white, orange to red depicts regions with increasingly suppressed order parameter and black lines depict the superconducting current density. Yellow arrow is a schematic depiction of an incoming single photon.

Figure 2

Histograms of the peak height of differentiated detection waveforms corresponding to detection of n-photon signal. The two curves correspond to light wave packets with different mean detected photon number $\mathsf{\mu }$. The arrows with corresponding error bars show predicted values of the peaks from the electro-thermal model and finite-bandwidth amplifiers. Figure reproduced from Cahal, et al., Optica 4, 1534–1535 (2017) [108].

Figure 3

(a) A two SNSPD-layer device with optical image (left) of the whole structure and a schematic cross-sectional view in top-right and a SEM image of the SNSPD itself (bottom-right). Figure reproduced from Verma, et al., Appl. Phys. Lett. 108, 131108 (2016) [114]. (b) Schematic of representation of a three SNSPD-layer device. Figure reproduced from Florya, et al., Low Temperature Physics 44, 221–225 (2018) [112].

Figure 4

Approximate thermal hotspot radius $r_{hs}$ as a function of $\alpha$-particle kinetic energy in NbN film with $T_C$ = 8 K and W_0.76Si_0.24 film with T_C = 3.35 K. Both films are assumed to be held at $T_0=\frac{T_C}{2}$.

Figure 5

(a) Demonstration of capability of 100% detection efficiency of He⁺ particles with kinetic energies of 200 eV (square), 400 eV (circle), 600 eV (up-triangle), 800 eV (down-triangle) and 1000 eV (diamond). The points I_kb corresponds to bias current value where the primary cause for hot-spot expansion changes from fluctuation-based into current-crowding regime. (b) Relative detection efficiency as a function of accumulated deposition time of neutral He atoms. Figures reproduced from Sclafani, et al., Nanotechnology 23, 065501 (2012) [153].

Figure 6

(a) Map of detection efficiency across the SNSPD pixel (left) under bombardment of 20 keV electrons, with a zoom in on a small part of the meander showing the non-zero detection probability outside of the superconducting meander. (b) A parameter sweep map that show the electron detection efficiency as a function of the reduced device bias current I/I_C and electron kinetic energy E_e. Figures reproduced from Rosticher, et al., Appl. Phys. Lett. 97, 183106 (2010) [154].