Change search
Link to record
Permanent link

Direct link
BETA
Publications (10 of 14) Show all publications
Gourgues, R., Zadeh, I. E., Elshaari, A. W., Bulgarini, G., Los, J. W. N., Zichi, J., . . . Zwiller, V. (2019). Controlled integration of selected detectors and emitters in photonic integrated circuits. Optics Express, 27(3), 3710-3716
Open this publication in new window or tab >>Controlled integration of selected detectors and emitters in photonic integrated circuits
Show others...
2019 (English)In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 27, no 3, p. 3710-3716Article in journal (Refereed) Published
Abstract [en]

Integration of superconducting nanowire single-photon detectors and quantum sources with photonic waveguides is crucial for realizing advanced quantum integrated circuits. However, scalability is hindered by stringent requirements on high-performance detectors. Here we overcome the yield limitation by controlled coupling of photonic channels to pre-selected detectors based on measuring critical current, timing resolution, and detection efficiency. As a proof of concept of our approach, we demonstrate a hybrid on-chip full-transceiver consisting of a deterministically integrated detector coupled to a selected nanowire quantum dot through a filtering circuit made of a silicon nitride waveguide and a ring resonator filter, delivering 100 dB suppression of the excitation laser. In addition, we perform extensive testing of the detectors before and after integration in the photonic circuit and show that the high performance of the superconducting nanowire detectors, including timing jitter down to 23 +/- 3 ps, is maintained. Our approach is fully compatible with wafer-level automated testing in a cleanroom environment. 

Place, publisher, year, edition, pages
OPTICAL SOC AMER, 2019
National Category
Accelerator Physics and Instrumentation
Identifiers
urn:nbn:se:kth:diva-244523 (URN)10.1364/OE.27.003710 (DOI)000457585600163 ()30732386 (PubMedID)2-s2.0-85061015801 (Scopus ID)
Note

QC 20190403

Available from: 2019-04-03 Created: 2019-04-03 Last updated: 2019-05-21Bibliographically approved
Wengerowsky, S., Joshi, S. K., Steinlechner, F., Zichi, J., Dobrovolskiy, S. M., van der Molen, R., . . . Ursin, R. (2019). Entanglement distribution over a 96-km-long submarine optical fiber. Paper presented at AUSER JF, 1969, PHYSICAL REVIEW LETTERS, V23, P880. Proceedings of the National Academy of Sciences of the United States of America, 116(14), 6684-6688
Open this publication in new window or tab >>Entanglement distribution over a 96-km-long submarine optical fiber
Show others...
2019 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 116, no 14, p. 6684-6688Article in journal (Refereed) Published
Abstract [en]

Quantum entanglement is one of the most extraordinary effects in quantum physics, with many applications in the emerging field of quantum information science. In particular, it provides the foundation for quantum key distribution (QKD), which promises a conceptual leap in information security. Entanglement-based QKD holds great promise for future applications owing to the possibility of device-independent security and the potential of establishing global-scale quantum repeater networks. While other approaches to QKD have already reached the level of maturity required for operation in absence of typical laboratory infrastructure, comparable field demonstrations of entanglement-based QKD have not been performed so far. Here, we report on the successful distribution of polarization-entangled photon pairs between Malta and Sicily over 96 km of submarine optical telecommunications fiber. We observe around 257 photon pairs per second, with a polarization visibility above 90%. Our results show that QKD based on polarization entanglement is now indeed viable in long-distance fiber links. This field demonstration marks the longest-distance distribution of entanglement in a deployed telecommunications network and demonstrates an international submarine quantum communication channel. This opens up myriad possibilities for future experiments and technological applications using existing infrastructure.

Place, publisher, year, edition, pages
NATL ACAD SCIENCES, 2019
Keywords
quantum entanglement, quantum key distribution, quantum cryptography, polarization-entangled photons
National Category
Physical Sciences
Identifiers
urn:nbn:se:kth:diva-249792 (URN)10.1073/pnas.1818752116 (DOI)000463069900034 ()30872476 (PubMedID)2-s2.0-85064055529 (Scopus ID)
Conference
AUSER JF, 1969, PHYSICAL REVIEW LETTERS, V23, P880
Note

QC 20190424

Available from: 2019-04-24 Created: 2019-04-24 Last updated: 2019-05-28Bibliographically approved
Machhadani, H., Zichi, J., Bougerol, C., Lequien, S., Thomassin, J.-L., Mollard, N., . . . Monroy, E. (2019). Improvement of the critical temeprature of NbTiN films on III-nitride substrates. Superconductors Science and Technology, 32(035008)
Open this publication in new window or tab >>Improvement of the critical temeprature of NbTiN films on III-nitride substrates
Show others...
2019 (English)In: Superconductors Science and Technology, ISSN 0953-2048, E-ISSN 1361-6668, Vol. 32, no 035008Article in journal (Refereed) Published
Abstract [en]

In this paper, we study the impact of using III-nitride semiconductors (GaN, AlN) as substrates for ultrathin (11 nm) superconducting films of NbTiN deposited by reactive magnetron sputtering. The resulting NbTiN layers are (111)-oriented, fully relaxed, and they keep an epitaxial relation with the substrate. The higher critical superconducting temperature (T c = 11.8 K) was obtained on AlN-on-sapphire, which was the substrate with smaller lattice mismatch with NbTiN. We attribute this improvement to a reduction of the NbTiN roughness, which appears associated with the relaxation of the lattice misfit with the substrate. On AlN-on-sapphire, superconducting nanowire single photon detectors were fabricated and tested, obtaining external quantum efficiencies that are in excellent agreement with theoretical calculations.

National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-251750 (URN)10.1088/1361-6668/aaf99d (DOI)
Note

QC 20190802

Available from: 2019-05-21 Created: 2019-05-21 Last updated: 2019-10-17Bibliographically approved
Machhadani, H., Zichi, J., Bougerol, C., Lequien, S., Thomassin, J.-L., Mollard, N., . . . Monroy, E. (2019). Improvement of the critical temperature of NbTiN films on III-nitride substrates. Superconductors Science and Technology, 32(3), Article ID 035008.
Open this publication in new window or tab >>Improvement of the critical temperature of NbTiN films on III-nitride substrates
Show others...
2019 (English)In: Superconductors Science and Technology, ISSN 0953-2048, E-ISSN 1361-6668, Vol. 32, no 3, article id 035008Article in journal (Refereed) Published
Abstract [en]

In this paper, we study the impact of using III-nitride semiconductors (GaN, AlN) as substrates for ultrathin (11 nm) superconducting films of NbTiN deposited by reactive magnetron sputtering. The resulting NbTiN layers are (111)-oriented, fully relaxed, and they keep an epitaxial relation with the substrate. The higher critical superconducting temperature (T-c = 11.8 K) was obtained on AIN-on-sapphire, which was the substrate with smaller lattice mismatch with NbTiN. We attribute this improvement to a reduction of the NbTiN roughness, which appears associated with the relaxation of the lattice misfit with the substrate. On AlN-on-sapphire, superconducting nanowire single photon detectors were fabricated and tested, obtaining external quantum efficiencies that are in excellent agreement with theoretical calculations.

Place, publisher, year, edition, pages
IOP PUBLISHING LTD, 2019
Keywords
NbTiN, superconductor, GaN, AlN, single photon detector
National Category
Condensed Matter Physics
Identifiers
urn:nbn:se:kth:diva-244483 (URN)10.1088/1361-6668/aaf99d (DOI)000458129800001 ()2-s2.0-85062473569 (Scopus ID)
Note

QC 20190321

Available from: 2019-03-21 Created: 2019-03-21 Last updated: 2019-05-21Bibliographically approved
Zichi, J., Chang, J., Steinhauer, S., Von Fieandt, K., Los, J. W. N., Visser, G., . . . Zwiller, V. (2019). Optimizing the stoichiometry of ultrathin NbTiN films for high-performance superconducting nanowire single-photon detectors. Optics Express, 27(19), 26579-26587
Open this publication in new window or tab >>Optimizing the stoichiometry of ultrathin NbTiN films for high-performance superconducting nanowire single-photon detectors
Show others...
2019 (English)In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 27, no 19, p. 26579-26587Article in journal (Refereed) Published
Abstract [en]

The requirements in quantum optics experiments for high single-photon detection efficiency. low timing jitter, low dark count rate and short dead time have been fulfilled with the development of superconducting nanowire single-photon detectors. Although they offer a detection efficiency above 90%, achieving a high time resolution in devices made of amorphous materials is a challenge, particularly at temperatures above 0.8 K. Devices made from niobium nitride and niobium titanium nitride allow us to reach the best timing jitter but. in turn, have stronger requirements in terms of film quality to achieve a high efficiency. Here we take advantage of the flexibility of reactive co-sputter deposition to tailor the composition of NbxTi1-xN superconducting films and show that a Nb fraction of x = 0.62 allows for the fabrication of detectors from films as thick as 9 nm and covering an active area of 20 mu m. with a wide detection saturation plateau at telecom wavelengths and in particular at 1550 nm. This is a signature of an internal detection efficiency saturation, achieved while maintaining the high time resolution associated with NbTiN and operation at 2.5K. With our optimized recipe, we reliably fabricated detectors with high critical current densities reaching a saturation plateau at 1550 nm with 80% system detection efficiency and with a FWHM timing jitter as low as 19.5 ps. Open Access Publishing Agreement

Place, publisher, year, edition, pages
OPTICAL SOC AMER, 2019
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-261307 (URN)10.1364/OE.27.026579 (DOI)000486373100026 ()2-s2.0-85072623051 (Scopus ID)
Note

QC 20191008

Available from: 2019-10-08 Created: 2019-10-08 Last updated: 2019-10-16Bibliographically approved
Gourgues, R., Los, J. W. N., Zichi, J., Chang, J., Kalhor, N., Bulgarini, G., . . . Zadeh, I. E. (2019). Superconducting nanowire single photon detectors operating at temperature from 4 to 7 K. Optics Express, 27(17), 24601-24609
Open this publication in new window or tab >>Superconducting nanowire single photon detectors operating at temperature from 4 to 7 K
Show others...
2019 (English)In: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 27, no 17, p. 24601-24609Article in journal (Refereed) Published
Abstract [en]

We experimentally investigate the performance of NbTiN superconducting nanowire single photon detectors above the base temperature of a conventional Gifford-McMahon cryocooler (2.5 K). By tailoring design and thickness (8-13 nm) of the detectors, high performance, high operating temperature, single-photon detection from the visible to telecom wavelengths are demonstrated. At 4.3 K, a detection efficiency of 82 % at 785 nm wavelength and a timing jitter of 30 +/- 0.3 ps are achieved. In addition, for 1550 nm and similar operating temperature we measured a detection efficiency as high as 64 %. Finally, we show that at temperatures up to 7 K, unity internal efficiency is maintained for the visible spectrum. Our work is particularly important to allow for the large scale implementation of superconducting single photon detectors in combination with heat sources such as free-space optical windows, cryogenic electronics, microwave sources and active optical components for complex quantum optical experiments and bio-imaging.

Place, publisher, year, edition, pages
OPTICAL SOC AMER, 2019
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-259452 (URN)10.1364/OE.27.024601 (DOI)000482098300081 ()2-s2.0-85071112796 (Scopus ID)
Note

QC 20190923

Available from: 2019-09-23 Created: 2019-09-23 Last updated: 2019-09-23Bibliographically approved
Hu, X., Hu, N., Meng, Y., Zou, K., Xu, L., Lan, X., . . . Zwiller, V. (2019). Superconducting nanowire single-photon detectors at the infrared spectrum range: detection efficiency and timing jitter. In: Sadwick, LP Yang, T (Ed.), TERAHERTZ, RF, MILLIMETER, AND SUBMILLIMETER-WAVE TECHNOLOGY AND APPLICATIONS XII: . Paper presented at Conference on Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications XII, FEB 04-07, 2019, San Francisco, CA.
Open this publication in new window or tab >>Superconducting nanowire single-photon detectors at the infrared spectrum range: detection efficiency and timing jitter
Show others...
2019 (English)In: TERAHERTZ, RF, MILLIMETER, AND SUBMILLIMETER-WAVE TECHNOLOGY AND APPLICATIONS XII / [ed] Sadwick, LP Yang, T, 2019Conference paper, Published paper (Refereed)
Abstract [en]

This paper reviews some recent research progress in superconducting nanowire single-photon detectors (SNSPDs) at the infrared spectrum range, with particular emphasis on detection efficiency and timing jitter. For detection efficiency, we present fractal SNSPDs with reduced polarization sensitivity; for timing jitter, we present two mechanisms of device timing jitter - vortex-crossing-induced timing jitter and spatial-inhomogeneity-induced timing jitter.

Series
Proceedings of SPIE, ISSN 0277-786X ; 10917
National Category
Atom and Molecular Physics and Optics
Identifiers
urn:nbn:se:kth:diva-252998 (URN)10.1117/12.2516132 (DOI)000468819000026 ()2-s2.0-85066033378 (Scopus ID)978-1-5106-2477-1 (ISBN)
Conference
Conference on Terahertz, RF, Millimeter, and Submillimeter-Wave Technology and Applications XII, FEB 04-07, 2019, San Francisco, CA
Note

QC 20190619

Available from: 2019-06-19 Created: 2019-06-19 Last updated: 2019-06-19Bibliographically approved
Cheng, Y., Chi, X., Gu, C., Zou, K., Zichi, J., Chen, S., . . . Hu, X. (2018). Experimental demonstration of superconducting nanowire single-photon detectors integrated with current reservoirs. In: Optics InfoBase Conference Papers: . Paper presented at Conference on Lasers and Electro-Optics/Pacific Rim, CLEOPR 2018, 29 July 2018 through 3 August 2018. OSA - The Optical Society
Open this publication in new window or tab >>Experimental demonstration of superconducting nanowire single-photon detectors integrated with current reservoirs
Show others...
2018 (English)In: Optics InfoBase Conference Papers, OSA - The Optical Society , 2018Conference paper, Published paper (Refereed)
Abstract [en]

We experimentally demonstrate the superconducting nanowire single-photon detectors integrated with current reservoirs that function as low-noise pre-amplifiers to increase the signal-to-noise ratio of detectors' outputs.

Place, publisher, year, edition, pages
OSA - The Optical Society, 2018
National Category
Physical Sciences
Identifiers
urn:nbn:se:kth:diva-246523 (URN)2-s2.0-85059384459 (Scopus ID)9781943580453 (ISBN)
Conference
Conference on Lasers and Electro-Optics/Pacific Rim, CLEOPR 2018, 29 July 2018 through 3 August 2018
Note

QC 20190402

Available from: 2019-04-02 Created: 2019-04-02 Last updated: 2019-04-02Bibliographically approved
Gu, C., Chi, X., Cheng, Y., Zichi, J., Hu, N., Lan, X., . . . Hu, X. (2018). Fractal superconducting nanowire single-photon detectors with low polarization sensitivity. In: Optics InfoBase Conference Papers: . Paper presented at CLEO: QELS_Fundamental Science, CLEO_QELS 2018, 13 May 2018 through 18 May 2018. Optical Society of America
Open this publication in new window or tab >>Fractal superconducting nanowire single-photon detectors with low polarization sensitivity
Show others...
2018 (English)In: Optics InfoBase Conference Papers, Optical Society of America, 2018Conference paper, Published paper (Refereed)
Abstract [en]

We demonstrated a fractal superconducting nanowire single-photon detector and achieved 42% device efficiency and 1.04 polarization sensitivity. The low polarization sensitivity can be maintained for higher-order spatial modes in few-mode optical fibers.

Place, publisher, year, edition, pages
Optical Society of America, 2018
Keywords
Acoustooptical devices, Avalanche photodiodes, Fractals, Nanowires, Optical fibers, Photons, Polarization, Device efficiency, Higher-order, Low polarization-sensitivity, Polarization sensitivity, Spatial modes, Superconducting nanowire single photon detectors, Particle beams
National Category
Other Physics Topics
Identifiers
urn:nbn:se:kth:diva-236363 (URN)10.1364/CLEO_QELS.2018.FW3F.1 (DOI)2-s2.0-85048934424 (Scopus ID)9781557528209 (ISBN)
Conference
CLEO: QELS_Fundamental Science, CLEO_QELS 2018, 13 May 2018 through 18 May 2018
Note

QC 20181106

Available from: 2018-11-06 Created: 2018-11-06 Last updated: 2018-12-17Bibliographically approved
Chi, X., Zou, K., Gu, C., Zichi, J., Cheng, Y., Hu, N., . . . Hu, X. (2018). Fractal superconducting nanowire single-photon detectors with reduced polarization sensitivity. Optics Letters, 43(20), 5017-5020
Open this publication in new window or tab >>Fractal superconducting nanowire single-photon detectors with reduced polarization sensitivity
Show others...
2018 (English)In: Optics Letters, ISSN 0146-9592, E-ISSN 1539-4794, Vol. 43, no 20, p. 5017-5020Article in journal (Refereed) Published
Abstract [en]

We demonstrate superconducting nanowire single-photon detectors (SNSPDs) based on a fractal design of the nanowires to reduce the polarization sensitivity of detection efficiency. We patterned niobium titanium nitride thin films into Peano curves with a linewidth of 100 nm and integrated the nanowires with optical microcavities to enhance their optical absorption. At a base temperature of 2.6 K, the fractal SNSPD exhibited a polarization-maximum device efficiency of 67% and a polarization-minimum device efficiency of 61% at a wavelength of 1550 nm. Therefore, the polarization sensitivity, defined as their ratio, was 1.1, lower than the polarization sensitivity of the SNSPDs in the meander design. The reduced polarization sensitivity of the detector could be maintained for higher-order spatial modes in multimode optical fibers and could tolerate misalignment between the optical mode and the detector. This fractal design is applicable to both amorphous and polycrystalline materials that are commonly used for making SNSPDs.

Place, publisher, year, edition, pages
OPTICAL SOC AMER, 2018
National Category
Other Engineering and Technologies
Identifiers
urn:nbn:se:kth:diva-238121 (URN)10.1364/OL.43.005017 (DOI)000447265700042 ()30320808 (PubMedID)2-s2.0-85054897619 (Scopus ID)
Note

QC 20181120

Available from: 2018-11-20 Created: 2018-11-20 Last updated: 2019-09-24Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0003-1831-2208

Search in DiVA

Show all publications