Ultrafast reset time of superconducting single photon detectors

Abstract

We have measured the ultrafast reset time of NbN superconducting single photon detectors (SSPDs) based on a design consisting of N parallel superconducting stripes. Compared to a standard SSPD of identical active area, the parallel SSPD displays a similar detection efficiency and a kinetic inductance, which is divided by N2. For N=12, the duration of the voltage detection pulse is reduced by nearly two orders of magnitude down to 200ps. The timing jitter associated with the rising front is only 16ps. These results open a way to efficient detectors with ultrahigh counting rate exceeding 1 GHz.

Photon-Number-Resolution at Telecom Wavelength with Superconducting Nanowires

“…The pulses show a full width at half maximum (FWHM) as low as 660ps. In a traditional 10x10 m 2 SSPD, the pulse width would be of the order of 10 ns FWHM, so the recovery of the output current I out through the amplifier input resistance is a factor ~4 2 faster (see section 5.3), which agrees with results reported by other groups (Gol'tsman et al 2007;Tarkhov et al 2008). As shown in section 5.3, the very attractive N 2 scaling rule for the output pulse duration unfortunately does not apply to the device recovery time.…”

“…To quantify the speed of the device, we take f 0 =(t reset ) -1 as the maximum repetition frequency, where t reset is the time that I f needs to recover to 95% of the bias current after a detection event. According to the results presented above, which are in good agreement with experimental data (Figure 2.b), I out decays exponentially with the same time constant for any n ( out = f ), which, for a bare N-PND, is N 2 times shorter than a normal SSPD of the same surface (Gol'tsman et al 2007;Tarkhov et al 2008). This however does not relate with the speed of the device.…”

Nanowire superconducting single-photon detectors on GaAs for integrated quantum photonic applications

“…Superconducting singlephoton detectors ͑SSPDs͒, 5 based on the photon-induced creation of resistive regions ͑hot spots͒ in nanowires biased close to their critical current, have shown detection efficiencies of up to 30% at = 1.3 m, dark counts in the range of few hertz 5 and are extremely fast ͑with count rates approaching the gigahertz range͒. 6,7 SSPDs have so far been fabricated only on sapphire, 5 MgO, 8 and Si 9 substrates, which are not suitable for the integration with single photon sources. The fabrication of SSPDs on GaAs would enable integration with all the circuitry required for photonic quantum information processing, since GaAs readily lends itself to the largescale production of single-photon sources, 10 waveguides, interferometers, and phase modulators.…”

Nanophotonic technologies for single-photon devices

“…Different parallel nanowire geometry has also been used to obtain photon number−resolving (PNR) detector with an ultrashort response time [98,99]. The photon number reso− lution regime can be achieved mainly in two ways.…”

“…The capability of patterning at the nanometric scale has brought to the development of a new class of pho− ton detectors based on superconducting nanowires, called superconducting single−photon detectors (SSPDs) [24]. The SSPDs are promising candidates for all the applications mentioned above because they offer single photon sensitivi− ty from visible to mid−infrared wavelengths [25], low dark counts [25], short recovery time (high frequency operation) [26], and low timing jitter [27].…”