Superconducting nanowire single photon detectors fabricated from an amorphous Mo0.75Ge0.25 thin film

Verma, Varun B.; Lita, Adriana E.; Vissers, Michael; Marsili, Francesco; Pappas, David P.; Mirin, Richard P.; Nam, Sae Woo

doi:10.1063/1.4890277

Cited by 65 publications

(48 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Similar results can be achieved with devices from TaN which have intermediate T c values from 6 to 10 K and, consequently, the advantage of still being able to operate efficiently between 2 and 4 K [13][14][15][16]. Recent results obtained with detectors from amorphous superconducting films MoGe [17], WSi [18][19][20][21], and MoSi [22], which all have T c in the range from 5 to 7.5 K, retain the promise of significant improvement in both detection efficiency and spectral range, extending the sensitivity further into the infrared. So far, the highest detection efficiency (DE) reported for SNSPD of the order of 93% has been achieved with WSi [20].…”

Section: Introductionsupporting

confidence: 71%

Characteristics of superconducting tungsten silicide WxSi1−x for single photon detection

et al. 2016

View full text Add to dashboard Cite

Superconducting properties of three series of amorphous W x Si 1x films with different thickness and stoichiometry were investigated by dc transport measurements in a magnetic field up to 9 T. These amorphous W x Si 1x films were deposited by magnetron cosputtering of the elemental source targets onto silicon substrates at room temperature and patterned in the form of bridges by optical lithography and reactive ion etching. Analysis of the data on magnetoconductivity allowed us to extract the critical temperatures, superconducting coherence lengths, magnetic penetration depths, and diffusion constants of electrons in the normal state as functions of film thickness for each stoichiometry. Two basic time constants were derived from transport and time-resolving measurements. A dynamic process of the formation of a hotspot was analyzed in the framework of a diffusion-based vortex-entry model. We used a two-stage diffusion approach and defined a hotspot size by assuming that the quasiparticles and normal-state electrons have the same diffusion constant. With this definition and these measured material parameters, the hotspot in the 5-nm-thick W 0.85 Si 0.15 film had a diameter of 107 nm at the peak of the number of nonequilibrium quasiparticles. Superconducting properties of three series of amorphous W x Si 1−x films with different thickness and stoichiometry were investigated by dc transport measurements in a magnetic field up to 9 T. These amorphous W x Si 1−x films were deposited by magnetron cosputtering of the elemental source targets onto silicon substrates at room temperature and patterned in the form of bridges by optical lithography and reactive ion etching. Analysis of the data on magnetoconductivity allowed us to extract the critical temperatures, superconducting coherence lengths, magnetic penetration depths, and diffusion constants of electrons in the normal state as functions of film thickness for each stoichiometry. Two basic time constants were derived from transport and time-resolving measurements. A dynamic process of the formation of a hotspot was analyzed in the framework of a diffusion-based vortex-entry model. We used a two-stage diffusion approach and defined a hotspot size by assuming that the quasiparticles and normal-state electrons have the same diffusion constant. With this definition and these measured material parameters, the hotspot in the 5-nm-thick W 0.85 Si 0.15 film had a diameter of 107 nm at the peak of the number of nonequilibrium quasiparticles.

show abstract

Section: Introductionsupporting

confidence: 71%

Characteristics of superconducting tungsten silicide WxSi1−x for single photon detection

et al. 2016

View full text Add to dashboard Cite

show abstract

“…11 One recent important advance in the SNSPD field has been the introduction of amorphous superconductors such as tungsten silicide (WSi), 12 molybdenum silicide (MoSi) 13,14 and molybdenum germanium (MoGe). 15 SNSPDs based on these materials currently have the highest reported detection efficiencies (93% for WSi 12 ), as well as a higher fabrication yield 16 than devices made of polycrystalline materials such as niobium nitride (NbN), 1 niobium titanium nitride (NbTiN) 17 and tantalum nitride (TaN). 18 MoSi SNSPDs tailored to specific advanced photon counting applications have recently been reported, including integration on an optical waveguide, 19 UV single-photon detection 20 and integrated ion trapping.…”

mentioning

confidence: 99%

Optically probing the detection mechanism in a molybdenum silicide superconducting nanowire single-photon detector

Caloz

Korzh

Timoney

et al. 2017

Applied Physics Letters

View full text Add to dashboard Cite

We experimentally investigate the detection mechanism in a meandered molybdenum silicide (MoSi) superconducting nanowire single-photon detector by characterising the detection probability as a function of bias current in the wavelength range of 750 to 2050 nm. Contrary to some previous observations on niobium nitride (NbN) or tungsten silicide (WSi) detectors, we find that the energycurrent relation is nonlinear in this range. Furthermore, thanks to the presence of a saturated detection efficiency over the whole range of wavelengths, we precisely quantify the shape of the curves. This allows a detailed study of their features, which are indicative of both Fano fluctuations and position-dependent effects.

show abstract

“…based on niobium nitride (NbN) nanowires present high speed, low dark counts, and low jitter. 3,4 Compared to more efficient SSPDs recently obtained from amorphous superconducting materials, [5][6][7][8][9] NbN SSPDs allow operation at higher temperatures and with simpler read-out circuitry. Due to such favourable combination, SSPDs have brought a breakthrough in fields such as quantum key distribution (QKD), 10,11 nanoscale imaging, 12 and quantum optics.…”

mentioning

confidence: 99%

Inhomogeneous critical current in nanowire superconducting single-photon detectors

et al. 2014

View full text Add to dashboard Cite

A superconducting thin film with uniform properties is the key to realize nanowire superconducting single-photon detectors (SSPDs) with high performance and high yield. To investigate the uniformity of NbN films, we introduce and characterize simple detectors consisting of short nanowires with length ranging from 100nm to 15μm. Our nanowires, contrary to meander SSPDs, allow probing the homogeneity of NbN at the nanoscale. Experimental results, endorsed by a microscopic model, show the strongly inhomogeneous nature of NbN films on the sub-100nm scale.

show abstract

Superconducting nanowire single photon detectors fabricated from an amorphous Mo0.75Ge0.25 thin film

Cited by 65 publications

References 36 publications

Characteristics of superconducting tungsten silicide WxSi1−x for single photon detection

Characteristics of superconducting tungsten silicide WxSi1−x for single photon detection

Optically probing the detection mechanism in a molybdenum silicide superconducting nanowire single-photon detector

Inhomogeneous critical current in nanowire superconducting single-photon detectors

Contact Info

Product

Resources

About