Low-jitter single flux quantum signal readout from superconducting single photon detector

doi:10.1364/OE.20.020115

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Low-jitter single flux quantum signal readout from superconducting single photon detector

Hirotaka Terai, Taro Yamashita, Shigehito Miki, Kazumasa Makise, and Zhen Wang »View Author Affiliations

Optics Express, Vol. 20, Issue 18, pp. 20115-20123 (2012)
http://dx.doi.org/10.1364/OE.20.020115

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Abstract

We developed a single-flux-quantum (SFQ) readout technology for superconducting single-photon detectors (SSPDs) to achieve low-jitter signal readout. By optimizing circuit parameters of the SFQ readout circuit, the input current sensitivity was improved below 10 μA, which is smaller than a typical critical current of SSPD. The experiment using a pulse-pattern generator as an input pulse source revealed that the measured jitter of the SFQ readout circuit is well below the system jitter of our measurement setup for the input current level above 15 μA. The measured jitter of the SSPD connected to the SFQ readout circuit was 37 ps full width at half maximum (FWHM) for an SSPD bias current of around 18 μA, which is a significant improvement on 67 ps FWHM jitter observed in conventional readout without an SFQ readout circuit.

1. Introduction

Superconducting single-photon detectors (SSPDs) made of niobium nitride (NbN) nanowire have attracted attention because of their high detection efficiency (DE) at near-infrared wavelengths, high counting rate, low dark count rate (DCR), wide detectable wavelength range and low timing jitter [1

G. Gol’tsman, O. Okunev, G. Chulkova, A. Lipatov, A. Semenov, K. Smirnov, B. Voronov, A. Dzardanov, C. Williams, and R. Sobolewski, “Picosecond superconducting single-photon optical detector,” Appl. Phys. Lett. 79(6), 705–707 (2001). [CrossRef]

]. Of these features, the low timing jitter is especially important in many applications, such as quantum key distribution (QKD) systems [2

H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki, and Y. Yamamoto, “Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors,” Nat. Photonics 1(6), 343–348 (2007). [CrossRef]

–4

M. Sasaki, M. Fujiwara, H. Ishizuka, W. Klaus, K. Wakui, M. Takeoka, S. Miki, T. Yamashita, Z. Wang, A. Tanaka, K. Yoshino, Y. Nambu, S. Takahashi, A. Tajima, A. Tomita, T. Domeki, T. Hasegawa, Y. Sakai, H. Kobayashi, T. Asai, K. Shimizu, T. Tokura, T. Tsurumaru, M. Matsui, T. Honjo, K. Tamaki, H. Takesue, Y. Tokura, J. F. Dynes, A. R. Dixon, A. W. Sharpe, Z. L. Yuan, A. J. Shields, S. Uchikoga, M. Legré, S. Robyr, P. Trinkler, L. Monat, J.-B. Page, G. Ribordy, A. Poppe, A. Allacher, O. Maurhart, T. Länger, M. Peev, and A. Zeilinger, “Field test of quantum key distribution in the Tokyo QKD Network,” Opt. Express 19(11), 10387–10409 (2011). [CrossRef] [PubMed]

], space-to-ground communications [5

M. E. Grein, A. J. Kerman, E. A. Dauler, O. Shatrovoy, R. J. Molnar, D. Rosenberg, J. Yoon, C. E. DeVoe, D. V. Murphy, B. S. Robinson, and D. M. Boroson, “Design of a Ground-Based Optical Receiver for the Lunar Laser Communications Demonstration,” Int. Conf. on Space Optical Systems and Applications, 78–82 (2011).

], as well as light detection and ranging (LIDAR) systems [6

A. McCarthy, R. J. Collins, N. J. Krichel, V. Fernández, A. M. Wallace, and G. S. Buller, “Long-range time-of-flight scanning sensor based on high-speed time-correlated single-photon counting,” Appl. Opt. 48(32), 6241–6251 (2009). [CrossRef] [PubMed]

]. However, the intrinsic jitter of the SSPD is difficult to determine, because the measured jitter includes the jitter produced by the readout electronics.

Our past experiments reveal that the timing jitter of an SSPD depends on the bias current, which flows to the readout electronics during the resistive state of the nanowire. The timing jitter significantly increases as decreasing the bias current below 20 μA, while it is almost constant for a large bias current above 30 μA. In addition, a given amount of bias current gives rise to almost the same jitter, even for two different SSPDs with different I_C’s. These imply that the measured jitter is mainly determined by the current sensitivity of the readout electronics rather than the intrinsic jitter. As a result, the timing jitter of an SSPD depends on its critical current (I_C), because the bias current is set below the I_C. On the other hand, a higher DE is attainable for an SSPD with a thinner NbN film and/or narrower wire, both of which decrease the I_C of the SSPD, resulting in a larger jitter. Thus, readout electronics with a higher current sensitivity are highly desirable for achieving both a high DE and low jitter.

A single-flux-quantum (SFQ) logic circuit operating at cryogenic temperatures is a promising technology for signal readout from the SSPD [7

S. Miki, H. Terai, T. Yamashita, K. Makise, M. Fujiwara, M. Sasaki, and Z. Wang, “Superconducting single-photon detectors integrated with single flux quantum readout circuits in a cryocooler,” Appl. Phys. Lett. 99(11), 111108 (2011). [CrossRef]

–11

T. Yamashita, S. Miki, H. Terai, K. Makise, and Z. Wang, “Crosstalk-free operation of multi-element SSPD array integrated with SFQ circuit in a 0.1 W GM cryocooler,” Opt. Lett. 37, 2982–2984 (2012). [CrossRef] [PubMed]

]. The original purpose of utilizing the SFQ circuit was to reduce the number of output cables from a multi-element SSPD by processing the output signals in a cryogenic environment [8

H. Terai, S. Miki, and Z. Wang, “Readout electronics using single-flux-quantum circuit technology for superconducting single-photon detector array,” IEEE Trans. Appl. Supercond. 19(3), 350–353 (2009). [CrossRef]

], but low-jitter operation of the SFQ circuit is also attractive for signal readout from the SSPD. We have already demonstrated SFQ readout operation from the SSPD [7

, 9

H. Terai, S. Miki, T. Yamashita, K. Makise, and Z. Wang, “Demonstration of single-flux-quantum readout operation for superconducting single-photon detectors,” Appl. Phys. Lett. 97(11), 112510 (2010). [CrossRef]

]; however, the advantage of employing the SFQ readout circuit to achieve low-jitter readout has not yet been demonstrated. This is mainly due to the lack of current sensitivity of a front-end circuit called the magnetically coupled DC/SFQ (MC-DC/SFQ) converter, because the timing jitter observed in the SFQ readout strongly depends on the input pulse amplitude and a lower amplitude results in a higher timing jitter.

In this letter, we report on the improvement of the current sensitivity and the timing jitter of the SFQ readout circuit. A careful re-optimization of circuit parameters in the MC-DC/SFQ converter significantly improves the input current sensitivity. The resulting SFQ readout circuit timing jitter is reduced well below the system jitter of our measurement setup. The timing jitter of the SSPD measured with the SFQ readout circuit is dramatically reduced compared to that measured by a conventional readout using a bias tee and a low-noise amplifier (LNA) operated at room temperature.

2. Circuit parameter optimization for low-jitter readout

Figure 1(a) shows the equivalent circuit of the MC-DC/SFQ converter. The operation of the MC-DC/SFQ converter is as follows. First, the Josephson junction J2 switches at the rising edge of an input pulse, generating an SFQ propagating to the right. At the same time, another SFQ is stored in the superconducting loop including the inductor L2, which generates a current circulating anti-clockwise in the L2 loop and prevents double-switching of J2 even at the peak level of the input pulse. At the falling edge of the input pulse, the stored SFQ in the L2 loop is canceled out by the switching of J1 and the circuit returns to the initial state. Thus, an input pulse is converted into a single SFQ pulse.

Fig. 1 (a) Equivalent circuit of MC-DC/SFQ converter. (b) Operating margin of MC-DC/SFQ converters with I_CJ1 = 100 μA, 130 μA, and 140 μA.

In the previous design, the I_C’s of J1 and J2 (I_CJ1 and I_CJ2) were set at 100 μA, which is the smallest value allowed in an SRL 2.5 kA/cm² Nb standard process [12

S. Nagasawa, Y. Hashimoto, H. Numata, and S. Tahara, “A 380 ps, 9.5 mW Josephson 4-Kbit RAM operated at a high bit yield,” IEEE Trans. Appl. Supercond. 5(2), 2447–2452 (1995). [CrossRef]

]. The area surrounded by the black line in Fig. 1(b) indicates the operating region experimentally obtained for the previous MC-DC/SFQ converter. The vertical and horizontal axes in Fig. 1(b) are the current amplitude of the input pulse (I_P) and the dc bias current of the MC-DC/SFQ converter (I_BDS), respectively.The operating region of I_P decreases as I_BDS increases, indicating that higher current sensitivity is attainable for higher I_BDS. Here the current sensitivity is the lowest I_Pvalue in the operating I_P region for a given I_BDS. In the previous MC-DC/SFQ converter with I_CJ1 = I_CJ2 = 100 μA, the operating region of I_P ends for an I_BDS above 0.89 mA and the resulting maximum current sensitivity was as large as 14 μA. We found that the malfunction of I_BDS above 0.89 mA results from the undesirable switching of J1 immediately after the switching of J2, which causes J2 to switch again generating two SFQ pulses at the rising edge of the input pulse. To avoid this malfunction, the I_CJ1 must be increased as much as possible. The areas surrounded by the red line and the blue line in Fig. 1(b) respectively indicate the measured operating regions of the redesigned MC-DC/SFQ converters with the I_CJ1’s of 130 μA and 140 μA, where all circuit parameters other than I_CJ1 are kept constant. The maximum current sensitivity for an I_CJ1 of 140 μA is less than 10 μA at an I_BDS above 0.95 mA.

On the other hand, the lower margin of I_BDS is restricted by missing errors on J1 switching at the falling edge of input pulses, which prevents the reset operation to the initial state. As shown in Fig. 1(b), the lower margin of I_BDS increases with increasing I_CJ1. We have never attempted to use an I_CJ1 of 150 μA, but the circuit simulation revealed that the lower limit of I_BDS for an I_CJ1 of 150 μA exceeds 0.86 mA, resulting in too small an operating margin for I_BDS. To maintain an appropriate operating margin while achieving a high current sensitivity, we determined the optimal I_CJ1 value to be 140 μA.

3. Current sensitivity measurement

To check the input current sensitivities of the MC-DC/SFQ converters in detail, we measured the error rate (ER) of the SFQ readout circuit by using a pulse-pattern generator (PPG) and a pulse counter. The experimental setup is shown in Fig. 2 . The detailed design of the SFQ readout circuit other than the MC-DC/SFQ converter is described elsewhere [7

, 9

], but a brief review is given here. The SFQ readout circuit has four MC-DC/SFQ converters, one of which was used in this experiment. The data output from the PPG was input to the SFQ readout circuit and converted into the SFQ pulse by the MC-DC/SFQ converter. The generated SFQ pulses propagate from the MC-DC/SFQ converters to the voltage driver via Josephson transmission lines and confluence buffer (CB) gates, neither of which requires a clock pulse for operation [13

K. K. Likharev and V. K. Semenov, “RSFQ logic/memory family: a new Josephson junction technology for sub-terahertz clock frequency digital systems,” IEEE Trans. Appl. Supercond. 1(1), 3–28 (1991). [CrossRef]

]. The SFQ pulses are then converted into rectangular pulses with an amplitude of around 2.0 mV and a duration of around 0.8 ns by the voltage driver for detection by the room temperature electronics. The SFQ readout circuit was dipped into liquid helium using a test probe with two 1.2 m long coaxial cables for input and output RF signals. To drive the SFQ readout circuit, a total bias current of around 60 mA was supplied through four cables. The output pulses from the voltage driver circuit were amplified by an LNA with the gain of 52 dB and detected by the pulse counter. The return-zero pulse sequence of “111…” with the repetition frequency of 10 MHz was used for the measurement.

Fig. 2 Experimental setups for error rate and jitter measurement. Pulse counter used in the error rate measurement is replaced by TCSPC module in the jitter measurement. In both measurements, pulse-pattern generator is employed as a signal source.

Figure 3 shows the I_P dependences of the measured ERs. If we define the input current sensitivity as the lowest I_P value that gives the ERs below 10⁻⁶, the input current sensitivities are read as 13.8 μA, 10.4 μA and 8.2 μA for the I_CJ1 of 100 μA, 130 μA and 140 μA, respectively. The ER curves are fitted well by error functions, suggesting an existence of thermal noise. The standard deviations (σ’s) evaluated from the fitting are 0.45 μA, 0.48 μA and 0.52 μA for the I_CJ1 of 100 μA, 130 μA and 140 μA, which correspond to 2.64 μA, 2.81 μA and 3.05 μA taking the current gain of the input transformer (M/L₂ = 66.2 pH/11.3 pH = 5.86) into account. At the temperature of around 4.2 K, the σ corresponds to the thermal noise current given by (4k_BTB/R)^1/2, where k_B is the Boltzmann’s constant, R is shunt resistor of the J2, T is temperature, and B is the bandwidth over which the noise is measured. In the Josephson junctions, the B can be approximated by the plasma frequency f_p = (I_C/2πΦ₀C)^1/2, where Φ₀ is flux quantum and C is junction capacitance. Maezawa et al. reported that the relation between specific capacitance C_S and critical current density J_C of Nb/AlO_X/Nb junctions is given by 1/C_S = 0.20-0.043log₁₀J_C [14

M. Maezawa, M. Aoyagi, H. Nakagawa, I. Kurosawa, and S. Takada, “Specific capacitance of Nb/AlOx /Nb Josephson junctions with critical current densities in the range of 0.1–18 kA/cm²,” Appl. Phys. Lett. 66(16), 2134–2136 (1995). [CrossRef]

]. Using this equation, the f_p is calculated as 190 GHz for the J_C of 2.5 kA/cm², which gives the σ of 3.3 μA for T = 4.2 K and R = 3.7 Ω. This value roughly agrees with the experimentally obtained σ of 2.64~3.05 μA, supporting that the measured ER curves are quantitatively characterized by the thermal fluctuation model.

Fig. 3 Error rate curves for I_P observed in SFQ readout circuit with I_CJ1 = 100 μA, 130 μA and 140 μA.

4. Jitter measurement of SFQ readout circuit

We measured the timing jitter of the SFQ readout circuit by replacing the pulse counter to a time-correlated single photon counting (TCSPC) module with 1 ps time resolution. The complimentary data output of the PPG was input to the TCSPC module as a trigger. The time correlation between the trigger and the output from the SFQ readout circuit was recorded, creating a histogram of the pulse count. The timing jitter was defined as the full width at half maximum (FWHM) of the observed peak in the histogram. The histogram for the I_P above 15 μA showed a Gaussian shape, while a tail structure appeared for the I_P below 15 μA. This is due to a non-linear dependence of the J2 switching delay for the I_P in the small I_P range. This indicates that a Gaussian shape response of the SSPD does not affected by the SFQ readout if the bias current above 15 μA is applied to the SSPD.

The timing jitters for the MC-DC/SFQ converters with an I_CJ1 of 130 μA and 140 μA were measured, where I_BDS was set at the maximum value for each MC-DC/SFQ converter. Figure 4 shows the I_P dependence of the timing jitter. The timing jitter decreases as I_P increases and reaches the lowest value of around 30 ps for a sufficiently large I_P. To determine the origin of this residual jitter of 30 ps, we eliminated the SFQ readout circuit and measured the system jitter produced by the PPG, the LNA and the discriminator in the TCSPC module. The result is shown in the inset in Fig. 4. The system jitter depends on the input level of the LNA (V_INAMP). A V_INAMP of 2.0 mV, which corresponds to the output level from the SFQ voltage driver, gives a timing jitter of around 30 ps. This value is almost comparable with the residual jitter of 30 ps observed in the SFQ readout circuit, suggesting that the timing jitter produced by the SFQ readout circuit is not measurable by our experimental setup for sufficiently large I_P.

Fig. 4 I_P dependence of timing jitter observed in SFQ readout circuit with I_CJ1 = 130 μA and 140 μA.

On the other hand, a rapid increase of the timing jitter is observed for decreasing I_P due to the lack of current sensitivity of the MC-DC/SFQ converter. The rapid increase of the timing jitter starts below an I_P of around 15 μA for I_CJ1 = 140 μA, and below 20 μA for I_CJ1 = 130 μA. This conversely indicates that negligibly low-jitter readout is achievable for an I_P above 15 μA by employing the SFQ readout circuit with I_CJ1 = 140 μA. As a typical SSPD with an I_C of less than 20 μA exhibits a timing jitter of more than 60 ps, the SFQ readout is attractive for signal readout from the SSPD for an I_C of around 20 μA or less.

5. Jitter measurement of SSPD using SFQ readout circuit

We implemented the SFQ readout circuit with the SSPD on the same workspace in a 0.1 W Gifford-McMahon (GM) refrigerator. The experimental setup is shown in Fig. 5(a) . The SFQ readout circuit was connected to the SSPD via a 10 cm long RF cable with the bandwidth of up to 65 GHz. We used an SSPD with a detection area of 15 x 15 μm² and an I_C of around 18 μA. The fabrication of the SSPD and its implementation in the refrigerator, including the method of fiber coupling are described in detail elsewhere [15

S. Miki, T. Yamashita, M. Fujiwara, M. Sasaki, and Z. Wang, “Multichannel SNSPD system with high detection efficiency at telecommunication wavelength,” Opt. Lett. 35(13), 2133–2135 (2010). [CrossRef] [PubMed]

, 16

S. Miki, M. Fujiwara, M. Sasaki, B. Baek, A. J. Miller, R. H. Hadfield, S. S. Nam, and Z. Wang, “Large sensitive-area NbN nanowire superconducting single-photon detectors fabricated on single-crystal MgO substrates,” Appl. Phys. Lett. 92(6), 061116 (2008). [CrossRef]

]. The I_C of 18 μA is a reasonable value for a given thickness and width of the NbN nanowire, indicating that the the NbN nanowire does not include significant constrictions, which causes an increase of the timing jitter [17

J. A. O’Connor, M. G. Tanner, C. M. Natarajan, G. S. Buller, R. J. Warburton, S. Miki, Z. Wang, S. W. Nam, and R. H. Hadfield, “Spatial dependence of output pulse delay in a niobium nitride nanowire superconducting single-photon detector,” Appl. Phys. Lett. 98(20), 201116 (2011). [CrossRef]

]. The system DE was about 16% at DCR = 100. The DC bias current to the SSPD (I_SSPD) was supplied via a 5 kΩ resister fabricated on the SFQ chip without any bias tees, reproducing the same DE curves as those observed in our conventional readout as shown in Fig. 5(b). A 1550 nm wavelength pulsed laser with a 100 fs pulse width and 80 MHz repetition rate was used as the photon source, where the average number of photons was fully attenuated to below one per pulse. The temperature of the workspace was kept at around 2.4 K during the measurement.

Fig. 5 Experimental setups for measuring timing jitter of SSPD. (a) Readout using SFQ circuit. (b) Conventional readout using bias tee and LNA operating at room temperature.

The measured histogram has a Gaussian shape for the measurement both with and without the SFQ readout circuit as reported in our previous report [7

], while the histogram with the SFQ readout circuit deviated from a Gaussian shape for the I_SSPD below 15 μA for the reason described in section 4. Figure 6 shows the I_SSPD dependence of the FWHM jitter measured in the setup shown in Fig. 5(a) and 5(b). In our conventional readout without the SFQ circuit [18

M. Fujiwara, A. Tanaka, S. Takahashi, K. Yoshino, Y. Nambu, A. Tajima, S. Miki, T. Yamashita, Z. Wang, A. Tomita, and M. Sasaki, “Afterpulse-like phenomenon of superconducting single photon detector in high speed quantum key distribution system,” Opt. Express 19(20), 19562–19571 (2011). [CrossRef] [PubMed]

], the 50 Ω resistor is usually connected to the SSPD in parallel, and acts as an escape path for the I_SSPD when the SSPD goes into a resistive state known as “latching.” The effect of the 50 Ω parallel shunt is clearly seen in Fig. 6. The upper limit of I_SSPD is about 18 μA for the SSPD with the parallel shunt, and as large as 14.5 μA without the parallel shunt. During practical use of the SSPD, the 50 Ω shunt resistor is thus indispensable for achieving as high a DE as possible. However, the parallel shunt also makes the input current of the LNA half of I_SSPD, causing an increase of the timing jitter. The resulting timing jitter with the parallel shunt is as low as 67 ps even at the maximum I_SSPD of 18 μA. On the other hand, the timing jitters with the SFQ readout circuit are as low as 50 ps for an I_SSPD above 15 μA. The timing jitter at an I_SSPD of around 18 μA is 37 ps, which is significantly improved from the 67 ps measured for the conventional readout with the 50 Ω parallel shunt. Further, a timing jitter of 37 ps could not be achieved by the conventional readout without the 50 Ω shunt even if I_SSPD could be increased to 18 μA. Therefore, the SFQ readout circuit offers a great advantage for achieving a low-jitter signal readout form the SSPD while keeping the DE as high as possible.

Fig. 6 I_SSPD dependence of FWHM jitter of SSPD. The measured jitter is plotted for conventional readout with and without 50 Ω shunt resistor and for SFQ readout.

One may be concerned with the difference between the system jitter of 30 ps observed in the measurement using the PPG and the jitter of 37 ps observed in the measurement using the SSPD. If an intrinsic jitter produced by the SSPD is responsible for this difference, the intrinsic jitter is estimated as (37²-30²)^1/2 = 22 ps. However, we are not confident that the 7-ps difference of the jitter is only on account of the intrinsic jitter of the SSPD, because the jitter measured by using the PPG is almost constant at 30 ps for an I_P above 15 μA, while the jitter measured with the SSPD slowly decreases even for an I_SSPD above 15 μA. This suggests that the jitter produced by the SFQ circuit depends on not only the input pulse amplitude but also its shape. According to an observation using a sampling oscilloscope, the rising edge of the output pulse from the SSPD is measured as around 250 ps, while that from the PPG is around 50 ps. More detailed measurement will be necessary to determine the intrinsic jitter of the SSPD, but it is beyond the scope of this letter.

6. Conclusion

In summary, we demonstrated low-jitter signal readout from the SSPD by optimizing circuit parameters in the SFQ readout circuit. By increasing the I_CJ1 value in the MC-DC/SFQ converter, an input current sensitivity of 8.2 μA was achieved, which is a considerable improvement from the 13.8 μA obtained in the previous design. The measurement using a PPG showed that the SFQ readout circuit exhibits an unmeasurable jitter for an I_P above 15 μA, which was well below the system jitter of 30 ps in our experimental setup. The SFQ readout circuit was implemented with the SSPD in a 0.1 W GM refrigerator and directly connected to the SSPD without a bias tee. The FWHM jitter of the SSPD measured with the SFQ readout circuit was 37 ps, which was much lower than the 67 ps observed in our conventional readout using a bias tee and LNA operated at room temperature. These results show that SFQ readout technology is very attractive for not only signal processing of the multi-element SSPD but also low-jitter signal readout from SSPDs.

Acknowledgments

The authors would like to thank M. Sasaki and M. Fujiwara of the Quantum Information and Communication Technology Group of NICT for their fruitful discussion.

References and links

1.	G. Gol’tsman, O. Okunev, G. Chulkova, A. Lipatov, A. Semenov, K. Smirnov, B. Voronov, A. Dzardanov, C. Williams, and R. Sobolewski, “Picosecond superconducting single-photon optical detector,” Appl. Phys. Lett. 79(6), 705–707 (2001). [CrossRef]
2.	H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki, and Y. Yamamoto, “Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors,” Nat. Photonics 1(6), 343–348 (2007). [CrossRef]
3.	R. H. Hadfield, “Single-photon detectors for optical quantum information applications,” Nat. Photonics 3(12), 696–705 (2009). [CrossRef]
4.	M. Sasaki, M. Fujiwara, H. Ishizuka, W. Klaus, K. Wakui, M. Takeoka, S. Miki, T. Yamashita, Z. Wang, A. Tanaka, K. Yoshino, Y. Nambu, S. Takahashi, A. Tajima, A. Tomita, T. Domeki, T. Hasegawa, Y. Sakai, H. Kobayashi, T. Asai, K. Shimizu, T. Tokura, T. Tsurumaru, M. Matsui, T. Honjo, K. Tamaki, H. Takesue, Y. Tokura, J. F. Dynes, A. R. Dixon, A. W. Sharpe, Z. L. Yuan, A. J. Shields, S. Uchikoga, M. Legré, S. Robyr, P. Trinkler, L. Monat, J.-B. Page, G. Ribordy, A. Poppe, A. Allacher, O. Maurhart, T. Länger, M. Peev, and A. Zeilinger, “Field test of quantum key distribution in the Tokyo QKD Network,” Opt. Express 19(11), 10387–10409 (2011). [CrossRef] [PubMed]
5.	M. E. Grein, A. J. Kerman, E. A. Dauler, O. Shatrovoy, R. J. Molnar, D. Rosenberg, J. Yoon, C. E. DeVoe, D. V. Murphy, B. S. Robinson, and D. M. Boroson, “Design of a Ground-Based Optical Receiver for the Lunar Laser Communications Demonstration,” Int. Conf. on Space Optical Systems and Applications, 78–82 (2011).
6.	A. McCarthy, R. J. Collins, N. J. Krichel, V. Fernández, A. M. Wallace, and G. S. Buller, “Long-range time-of-flight scanning sensor based on high-speed time-correlated single-photon counting,” Appl. Opt. 48(32), 6241–6251 (2009). [CrossRef] [PubMed]
7.	S. Miki, H. Terai, T. Yamashita, K. Makise, M. Fujiwara, M. Sasaki, and Z. Wang, “Superconducting single-photon detectors integrated with single flux quantum readout circuits in a cryocooler,” Appl. Phys. Lett. 99(11), 111108 (2011). [CrossRef]
8.	H. Terai, S. Miki, and Z. Wang, “Readout electronics using single-flux-quantum circuit technology for superconducting single-photon detector array,” IEEE Trans. Appl. Supercond. 19(3), 350–353 (2009). [CrossRef]
9.	H. Terai, S. Miki, T. Yamashita, K. Makise, and Z. Wang, “Demonstration of single-flux-quantum readout operation for superconducting single-photon detectors,” Appl. Phys. Lett. 97(11), 112510 (2010). [CrossRef]
10.	T. Ortlepp, M. Hofherr, L. Fritzsch, S. Engert, K. Ilin, D. Rall, H. Toepfer, H. G. Meyer, and M. Siegel, “Demonstration of digital readout circuit for superconducting nanowire single photon detector,” Opt. Express 19(19), 18593–18601 (2011). [CrossRef] [PubMed]
11.	T. Yamashita, S. Miki, H. Terai, K. Makise, and Z. Wang, “Crosstalk-free operation of multi-element SSPD array integrated with SFQ circuit in a 0.1 W GM cryocooler,” Opt. Lett. 37, 2982–2984 (2012). [CrossRef] [PubMed]
12.	S. Nagasawa, Y. Hashimoto, H. Numata, and S. Tahara, “A 380 ps, 9.5 mW Josephson 4-Kbit RAM operated at a high bit yield,” IEEE Trans. Appl. Supercond. 5(2), 2447–2452 (1995). [CrossRef]
13.	K. K. Likharev and V. K. Semenov, “RSFQ logic/memory family: a new Josephson junction technology for sub-terahertz clock frequency digital systems,” IEEE Trans. Appl. Supercond. 1(1), 3–28 (1991). [CrossRef]
14.	M. Maezawa, M. Aoyagi, H. Nakagawa, I. Kurosawa, and S. Takada, “Specific capacitance of Nb/AlOx /Nb Josephson junctions with critical current densities in the range of 0.1–18 kA/cm²,” Appl. Phys. Lett. 66(16), 2134–2136 (1995). [CrossRef]
15.	S. Miki, T. Yamashita, M. Fujiwara, M. Sasaki, and Z. Wang, “Multichannel SNSPD system with high detection efficiency at telecommunication wavelength,” Opt. Lett. 35(13), 2133–2135 (2010). [CrossRef] [PubMed]
16.	S. Miki, M. Fujiwara, M. Sasaki, B. Baek, A. J. Miller, R. H. Hadfield, S. S. Nam, and Z. Wang, “Large sensitive-area NbN nanowire superconducting single-photon detectors fabricated on single-crystal MgO substrates,” Appl. Phys. Lett. 92(6), 061116 (2008). [CrossRef]
17.	J. A. O’Connor, M. G. Tanner, C. M. Natarajan, G. S. Buller, R. J. Warburton, S. Miki, Z. Wang, S. W. Nam, and R. H. Hadfield, “Spatial dependence of output pulse delay in a niobium nitride nanowire superconducting single-photon detector,” Appl. Phys. Lett. 98(20), 201116 (2011). [CrossRef]
18.	M. Fujiwara, A. Tanaka, S. Takahashi, K. Yoshino, Y. Nambu, A. Tajima, S. Miki, T. Yamashita, Z. Wang, A. Tomita, and M. Sasaki, “Afterpulse-like phenomenon of superconducting single photon detector in high speed quantum key distribution system,” Opt. Express 19(20), 19562–19571 (2011). [CrossRef] [PubMed]

OCIS Codes
(040.0040) Detectors : Detectors
(270.5570) Quantum optics : Quantum detectors

ToC Category:
Detectors

History
Original Manuscript: June 29, 2012
Revised Manuscript: August 10, 2012
Manuscript Accepted: August 15, 2012
Published: August 17, 2012

Citation
Hirotaka Terai, Taro Yamashita, Shigehito Miki, Kazumasa Makise, and Zhen Wang, "Low-jitter single flux quantum signal readout from superconducting single photon detector," Opt. Express 20, 20115-20123 (2012)
http://www.opticsinfobase.org/oe/abstract.cfm?URI=oe-20-18-20115

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References

G. Gol’tsman, O. Okunev, G. Chulkova, A. Lipatov, A. Semenov, K. Smirnov, B. Voronov, A. Dzardanov, C. Williams, and R. Sobolewski, “Picosecond superconducting single-photon optical detector,” Appl. Phys. Lett.79(6), 705–707 (2001). [CrossRef]
H. Takesue, S. W. Nam, Q. Zhang, R. H. Hadfield, T. Honjo, K. Tamaki, and Y. Yamamoto, “Quantum key distribution over a 40-dB channel loss using superconducting single-photon detectors,” Nat. Photonics1(6), 343–348 (2007). [CrossRef]
R. H. Hadfield, “Single-photon detectors for optical quantum information applications,” Nat. Photonics3(12), 696–705 (2009). [CrossRef]
M. Sasaki, M. Fujiwara, H. Ishizuka, W. Klaus, K. Wakui, M. Takeoka, S. Miki, T. Yamashita, Z. Wang, A. Tanaka, K. Yoshino, Y. Nambu, S. Takahashi, A. Tajima, A. Tomita, T. Domeki, T. Hasegawa, Y. Sakai, H. Kobayashi, T. Asai, K. Shimizu, T. Tokura, T. Tsurumaru, M. Matsui, T. Honjo, K. Tamaki, H. Takesue, Y. Tokura, J. F. Dynes, A. R. Dixon, A. W. Sharpe, Z. L. Yuan, A. J. Shields, S. Uchikoga, M. Legré, S. Robyr, P. Trinkler, L. Monat, J.-B. Page, G. Ribordy, A. Poppe, A. Allacher, O. Maurhart, T. Länger, M. Peev, and A. Zeilinger, “Field test of quantum key distribution in the Tokyo QKD Network,” Opt. Express19(11), 10387–10409 (2011). [CrossRef] [PubMed]
M. E. Grein, A. J. Kerman, E. A. Dauler, O. Shatrovoy, R. J. Molnar, D. Rosenberg, J. Yoon, C. E. DeVoe, D. V. Murphy, B. S. Robinson, and D. M. Boroson, “Design of a Ground-Based Optical Receiver for the Lunar Laser Communications Demonstration,” Int. Conf. on Space Optical Systems and Applications, 78–82 (2011).
A. McCarthy, R. J. Collins, N. J. Krichel, V. Fernández, A. M. Wallace, and G. S. Buller, “Long-range time-of-flight scanning sensor based on high-speed time-correlated single-photon counting,” Appl. Opt.48(32), 6241–6251 (2009). [CrossRef] [PubMed]
S. Miki, H. Terai, T. Yamashita, K. Makise, M. Fujiwara, M. Sasaki, and Z. Wang, “Superconducting single-photon detectors integrated with single flux quantum readout circuits in a cryocooler,” Appl. Phys. Lett.99(11), 111108 (2011). [CrossRef]
H. Terai, S. Miki, and Z. Wang, “Readout electronics using single-flux-quantum circuit technology for superconducting single-photon detector array,” IEEE Trans. Appl. Supercond.19(3), 350–353 (2009). [CrossRef]
H. Terai, S. Miki, T. Yamashita, K. Makise, and Z. Wang, “Demonstration of single-flux-quantum readout operation for superconducting single-photon detectors,” Appl. Phys. Lett.97(11), 112510 (2010). [CrossRef]
T. Ortlepp, M. Hofherr, L. Fritzsch, S. Engert, K. Ilin, D. Rall, H. Toepfer, H. G. Meyer, and M. Siegel, “Demonstration of digital readout circuit for superconducting nanowire single photon detector,” Opt. Express19(19), 18593–18601 (2011). [CrossRef] [PubMed]
T. Yamashita, S. Miki, H. Terai, K. Makise, and Z. Wang, “Crosstalk-free operation of multi-element SSPD array integrated with SFQ circuit in a 0.1 W GM cryocooler,” Opt. Lett.37, 2982–2984 (2012). [CrossRef] [PubMed]
S. Nagasawa, Y. Hashimoto, H. Numata, and S. Tahara, “A 380 ps, 9.5 mW Josephson 4-Kbit RAM operated at a high bit yield,” IEEE Trans. Appl. Supercond.5(2), 2447–2452 (1995). [CrossRef]
K. K. Likharev and V. K. Semenov, “RSFQ logic/memory family: a new Josephson junction technology for sub-terahertz clock frequency digital systems,” IEEE Trans. Appl. Supercond.1(1), 3–28 (1991). [CrossRef]
M. Maezawa, M. Aoyagi, H. Nakagawa, I. Kurosawa, and S. Takada, “Specific capacitance of Nb/AlOx /Nb Josephson junctions with critical current densities in the range of 0.1–18 kA/cm2,” Appl. Phys. Lett.66(16), 2134–2136 (1995). [CrossRef]
S. Miki, T. Yamashita, M. Fujiwara, M. Sasaki, and Z. Wang, “Multichannel SNSPD system with high detection efficiency at telecommunication wavelength,” Opt. Lett.35(13), 2133–2135 (2010). [CrossRef] [PubMed]
S. Miki, M. Fujiwara, M. Sasaki, B. Baek, A. J. Miller, R. H. Hadfield, S. S. Nam, and Z. Wang, “Large sensitive-area NbN nanowire superconducting single-photon detectors fabricated on single-crystal MgO substrates,” Appl. Phys. Lett.92(6), 061116 (2008). [CrossRef]
J. A. O’Connor, M. G. Tanner, C. M. Natarajan, G. S. Buller, R. J. Warburton, S. Miki, Z. Wang, S. W. Nam, and R. H. Hadfield, “Spatial dependence of output pulse delay in a niobium nitride nanowire superconducting single-photon detector,” Appl. Phys. Lett.98(20), 201116 (2011). [CrossRef]
M. Fujiwara, A. Tanaka, S. Takahashi, K. Yoshino, Y. Nambu, A. Tajima, S. Miki, T. Yamashita, Z. Wang, A. Tomita, and M. Sasaki, “Afterpulse-like phenomenon of superconducting single photon detector in high speed quantum key distribution system,” Opt. Express19(20), 19562–19571 (2011). [CrossRef] [PubMed]

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