Polarization-sensitive efficient superconducting nanowire single photon detector and design method therefor

Abstract

The invention discloses a polarization-sensitive efficient superconducting nanowire single photon detector and a design method therefor. The detector comprises a silicon substrate, a gold film reflective layer, a silicon dioxide medium cavity, an NbN nanowire and a coupling anti-symmetric split ring resonator, wherein the silicon substrate, the gold film reflective layer, the silicon dioxide medium cavity and the coupling anti-symmetric split ring resonator are arranged from the bottom up in sequence; the NbN nanowire is positioned in the interior of the silicon dioxide medium cavity; the NbN nanowire comprises multiple periodically-arranged unit structures; and the coupling anti-symmetric split ring resonator is periodically arranged. The invention also discloses a design method for the detector. The detector provided by the invention has a simple and creative structure, high width of the adopted superconducting material NbN nanowire, high duty ratio, high detection efficiency on near infrared wave single photons, and high counting speed.

Description

technical field [0001] The invention belongs to the fields of quantum communication, remote sensing and biological imaging, and in particular relates to a polarization-sensitive high-efficiency superconducting nanowire single-photon detector and a design method thereof. Background technique [0002] Compared with semiconductor detectors, the Superconducting Nanowire Single Photon Detector (SNSPD) working in the near-infrared band has the advantages of high efficiency, fast speed, low dark count and low jitter. This detector exhibits intrinsic polarization selectivity due to its meander-line structure. When we need to detect the intensity of light, we should reduce this polarization selectivity as much as possible. But when we use the polarization properties of light, such as the encryption of quantum keys, or measure the polarization properties of light, such as polarimetry in remote sensing imaging and polarization imaging in scattering media, we need a highly polarization...

AI Technical Summary

Problems solved by technology

At present, Yu Lixing et al. of Shanghai Institute of Microsystems are studying high PER SNSPDs, back incident Si-λ / 4SiO2-NbN cavity, and improving PER (up to 22) by reducing the width of NbN nanowires and reducing the duty cycle. However, the TE absorption rate is too low (12%)

In order to maintain a high PER while improving the absorption of TE waves, Mária Csete et al. added a nanocavity grating structure to a 100nm-wide NbN nanowire. When the duty cycle is 0.13, the TE absorption is below 45%, but the process of this structure is difficult. It is almost impossible to realize, which is very detrimental to the application of the device

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