Growth optimization of TaN for superconducting spintronics
Manuel Müller, Raphael Hoepfl, Lukas Liensberger, Stephan Geprägs, Hans Huebl, Mathias Weiler, Rudolf Gross, Matthias Althammer
GGrowth optimization of TaN for superconducting spintronics
M. M¨uller,
1, 2, a) R. Hoepfl,
1, 2
L. Liensberger,
1, 2
S. Gepr¨ags, H. Huebl,
1, 2, 3
M. Weiler,
4, 1, 2
R. Gross,
1, 2, 3 andM. Althammer
1, 2, b) Walther-Meißner-Institut, Bayerische Akademie der Wissenschaften, 85748 Garching,Germany Physik-Department, Technische Universit¨at M¨unchen, 85748 Garching, Germany Munich Center for Quantum Science and Technology (MCQST), Schellingstraße 4, 80799 M¨unchen,Germany Fachbereich Physik and Landesforschungszentrum OPTIMAS, Technische Universit¨at Kaiserslautern,67663 Kaiserslautern, Germany (Dated: February 19, 2021)
We have optimized the growth of superconducting TaN thin films on SiO substrates via dc magnetron sput-tering and extract a maximum superconducting transition temperature of T c = 5 K as well as a maximumcritical field µ H c2 = (13 . ± .
1) T. To investigate the impact of spin-orbit interaction in superconduc-tor/ferromagnet heterostructures, we then analyze the magnetization dynamics of both normal state andsuperconducting TaN/Ni Fe (Permalloy, Py)-bilayers as a function of temperature using broadband fer-romagnetic resonance (bbFMR) spectroscopy. The phase sensitive detection of the microwave transmissionsignal is used to quantitatively extract the inverse current-induced torques of the bilayers. The results arecompared to our previous study on NbN/Py-bilayers. In the normal state of TaN, we detect a positivedamping-like current-induced torque σ d from the inverse spin Hall effect (iSHE) and a small field-like torque σ f attributed to the inverse Rashba-Edelstein effect (iREE) at the TaN/Py-interface. In the superconduct-ing state of TaN, we detect a negative σ d attributed to the quasiparticle mediated inverse spin Hall effect(QMiSHE) and the unexpected manifestation of a large positive field-like σ f of unknown origin matching ourprevious results for NbN/Py-bilayers. I. INTRODUCTION
Superconducting spintronics is a rapidly growingresearch field. An important aspect is the investi-gation of methods for injecting angular momentuminto superconducting materials to benefit from thepotentially enhanced spin transport properties insuperconductors . First promising results include thedetection of extremely long spin lifetimes and largespin Hall angles (SHA) in superconductors as wellas the detection of enhanced spin transport propertiesin superconductor(SC)/ferromagnet(FM)-bilayers .An emerging direction within this young field is theinvestigation of superconductors with large spin-orbit in-teraction (SOI) or in proximity to heavy metals .This approach allows to study how SOI affects thesuperconducting and spin transport properties. Besidesthe generation of spin-triplet supercurrents , theoret-ical predictions include the generation of supercurrentsby Rashba-spin-orbit interaction , the generation ofMajorana quasiparticles and supercurrent-inducedspin-orbit torques . For the fabrication of high qual-ity superconducting spintronics devices, cheap, easyto fabricate and non-hazardous materials with largespin-orbit interaction are desirable. In this paper, wediscuss TaN as a potential candidate for spin-currentexperiments with superconductors, motivated by the a) [email protected] b) [email protected] large SOI induced by Ta . We present the growthoptimization of superconducting TaN deposited viareactive dc magnetron sputtering, a material whichotherwise finds application in long-wavelength singlephoton detectors , corrosion-resistive coatings and as a diffusion barrier against Cu . To investigatethe impact of spin-orbit interaction on the magnetizationdynamics parameters, we perform broadband ferromag-netic resonance (bbFMR) on TaN/Ni Fe (Permalloy,Py)-bilayers in the normal conducting (NC) and super-conducting (SC) state. The bbFMR experiments andin particular the frequency-dependent phase sensitiveanalysis of the transmission data allows to determinequantities such as the effective magnetization, magneticanisotropies, and magnetization damping . In ad-dition, this data also contains information about theelectrical ac currents which arise from magnetizationdynamics and can be attributed to inverse spin-orbittorques (iSOTs) as well as classical electrodynamics(i.e. Faraday’s law) . Both contributions can bequantified in terms of the complex inverse spin-orbittorque conductivity σ SOT , which relates the inducedcharge current in the sample to a change in magne-tization J ∝ σ SOT ∂ M /∂t . Hence, bbFMR allowsto simultaneously quantify the impact of an adjacentsuperconducting film in superconductor/ferromagneticmetal(FM)-heterostructures on both the magnetizationdynamics (e.g. FMR linewidth) in the FM and on thespin-orbit torque conductivity σ SOT = σ f + i · σ d , whichcomprises damping-like torques such as the inverse spinHall effect (iSHE) in σ d and field-like effects such as theinverse Rashba-Edelstein effect (iREE) and Faraday a r X i v : . [ c ond - m a t . m e s - h a ll ] F e b currents in σ f . Our analysis is based on Ref. 33 and wasadapted for SC/FM-heterostructures in our previouswork . Comparing our results on TaN/Py bilayers tothose of Ref. 32 reveals that SOI in TaN has a strongeffect on the σ SOT in the SC state. We in particularobserve a more strongly pronounced σ d in the super-conducting state of our TaN/Py-bilayer. This furthersupports our conjecture in Ref. 32, that a negative σ d inthe SC state originates from the quasiparticle mediatedinverse spin Hall effect (QMiSHE) . II. EXPERIMENTAL DETAILS
For this study, we grow 60 nm thick TaN thin filmson a thermally oxidized Si (100) substrate by reactivedc magnetron sputtering in a mixed Ar/N -atmosphere.For the SC/FM-heterostructures, Py was depositedin situ on TaN to prevent oxidation at the SC/FMinterface. Furthermore, a protecting TaO x cap layer hasbeen used resulting in TaN/Py/TaO x heterostructures.The thickness d TaO x of the TaO x cap layer is chosenthin enough to have no measurable effect on the iSOTconductivities ( d TaO x < <
300 pm) (see Fig. S1 of the Supplementary Material(SM) 37). For the determination of the resistivityand the superconducting transition temperature T c ,we performed 4-point transport measurements usingthe Van-der-Pauw-method on single layer TaN filmsas a function of temperature between 3 K and 300K. The exemplary data set in Fig. 1(a) shows theresistivity during the transition from the normal to thesuperconducting state. The gray dashed vertical linedefines T c = ( T + T ) / ρ takes on 90% ( ρ ( T ) /ρ NC =90%)and 10% ( ρ ( T ) /ρ NC =10%) of its normal state resistivity ρ NC at T = 7 K. This particular film was grown at agas flow ratio N /Ar=0.35, a deposition temperature T depo = 500 ◦ C, a deposition pressure p depo = 5 µ bar anda sputtering power P = 30 W, resulting in T c = 4 .
97 K.The area highlighted in blue marks the superconductingtransition width ∆ T c = T − T = 1 .
26 K.Additionally, we performed x-ray reflectometry measure-ments (see Fig. 1(b)) to determine the layer thickness d SC and volume density D V of our samples. For this par-ticular film, we find d SC ≈
64 nm and D V ≈ . / cm in agreement with the expected density for cubic TaN .In our experiments we used films with a thicknessranging between 54 and 66 nm. III. RESULTS AND DISCUSSIONA. Growth optimization of superconducting TaN (cid:1) ( mW m) T ( K ) T c (cid:1) T c ( a ) r a w d a t a s i m u l a t i o n I (arb. units) (cid:2) ( ° ) T c (K) N / A r T d e p o = 5 0 0 ° C p d e p o = 5 m b a r R = 1 . 1 Å / s D V (g/cm3) N / A r c - T a NN - r i c h p h a s e sT a - r i c h p h a s e sT a - r i c h p h a s e s N / A r = 0 . 3 5 p d e p o = 5 m b a r R = 1 . 1 Å / s T c (K) T d e p o ( (cid:176) C ) ( e ) ( d )( f )( b )( c ) D V (g/cm3) T d e p o ( (cid:176) C ) c - T a NN - r i c h p h a s e s
Figure 1. (a) Exemplary plot of the measured resistivity ρ versus temperature T together with the extracted supercon-ducting transition temperature T c (vertical dashed line) andtransition width ∆ T c (blue area). (b) Exemplary x-ray reflec-tometry data (black) and simulation curve (red) allowing toextract the layer thickness d TaN as well as the volume density D V of the TaN thin films. (c), (d) Superconducting transitiontemperature T c and volume density D V of the TaN thin filmsas a function of the N / Ar-flow ratio during deposition. (e),(f) T c and D V as a function of the deposition temperature T depo . Samples that did not exhibit full superconductivityabove T = 3 K are represented by red arrows in (c) and (e)as well as red squares in (d) and (f). In order to optimize their superconducting properties,we deposited TaN-films at a deposition temperatureof T depo = 500 ◦ C and a pressure of p = 5 µ bar atvarying N / Ar flow ratios during deposition. Figure1(c) shows the transition temperature T c as function ofthe N /Ar-flow ratio during the deposition. For flowratios (0 . ≤ N / Ar ≤ . T c of the TaNthin films above 3 K. In addition, we mark gas flowmixtures that did not exhibit full superconductivityabove T = 3 K by red arrows. For this optimizationseries, we find a maximum of T c = 4 .
97 K at a gasflow ratio of N / Ar = 0 .
35. Notably, this ratio issignificantly higher compared to earlier studies ,which predict a maximal T c of TaN at gas flow ratiosN /Ar = 0.10-0.15. This difference can have variousreasons such as a different distance between target andsubstrate or different values of the kinetic energy of theTa-atoms during the sputtering process due to varyingsputtering power P and target bias voltage (see Fig. S2of the SM ).From the extracted volume density D V in Fig. 1(d), wecan identify three regimes with different TaN phases inagreement with the results in Ref. 27. In particular,we find non-superconducting regimes for low and highN -concentrations, which we attribute to the formationof Ta- and N-rich TaN ± δ phases such as Ta N andTaN for low and high N2/Ar-ratios, respectively.The intermediate range (13 . ≤ D V ≤ .
7) g / cm isattributed to the cubic TaN-phase (c-TaN) . In thefabricated films, all three phases may be present inparallel, with varying volume fractions, since in ourexperiments we only can determine the average volumedensity. For the optimized samples with the highest T c ,however, we expect a high fraction of our thin films to bein the c-TaN phase. In Fig. 1(e), we plot the T c of ourthin films as a function of the deposition temperature T depo for p = 5 µ bar and N /Ar=0.35. It becomesapparent that superconducting films with a T c higherthan 3 K were found only for T depo > ◦ C. Figure 1(f)suggests that this threshold in temperature coincideswith the transition of our samples from N-rich TaN δ to the c-TaN phase. Consequently, the optimized growthparameters for superconducting TaN with a high T c are N /Ar=0.35, T depo = 500 ◦ C , p depo = 5 µ bar and P depo = 30 W. Our maximum T c values are smallerthan those reported in Ref. 42, where T c = 6 K wasachieved for c-TaN films grown on SiO using infraredpulsed laser deposition. TaN is known to have evenhigher superconducting transition temperatures of upto T c = 10 . O (sapphire) and MgO , where films with a bettertexture can be achieved. However, our optimal T c valuesfor TaN are in agreement with previous results,indicatingthat thermally oxidized Si is not an ideal substrate forthe growth of TaN with maximum T c values . To con-firm this suggestion, we utilized the optimized growthparameters to deposit TaN films on c-plane sapphiresubstrates and obtained T c =7.72 K for a 60 nm thickTaN film. For these films we also found reflections fromthe c-TaN-phase by x-ray diffraction (see Fig. S3of the SM ). We note, however, that the purpose ofthis study is not to maximize T c but to compare thespin-orbit torques arising from superconducting TaN tothose that we previously reported for NbN also grownon SiO . B. Critical magnetic field of optimized TaN films
To analyze the magnetic field dependence of the su-perconducting properties of our TaN-films, we measuredresistivity vs. temperature curves of our optimized TaNthin film (N /Ar=0.35, T depo = 500 ◦ C, p depo = 5 µ barand P depo = 30 W, d = 60 nm), for fixed in-plane mag-netic fields in the range between 0 and 12 T. The resultis shown in Fig. 2(a). We observe a reduction in T c as well as an increase of the superconducting transitionwidth with increasing external magnetic field strength µ H ext . In Fig. 2(b) we plot the transition tempera- (cid:1) (µ W m) T ( K )
0 T3 T6 T9 T1 2 T ( a ) ( b ) T c T e x p oc µ H c2 (T) T / T c µ H c 2 ( 0 ) = ( 1 3 . 8 ± 0 . 1 ) T Figure 2. (a) Resistivity ρ as a function of temperature T measured in an external in-plane magnetic field µ H ext fora TaN film fabricated using the optimized parameters. (b)Extracted critical field µ H c2 ( T ) (black and blue dots) as afunction of reduced temperature T /T c together with the fit-ted behavior of µ H c2 ( T ) following Eq. (1). The blue datapoints indicate the linearly extrapolated T c for high exter-nal magnetic fields, where the SC thin film did not exhibitfull superconductivity for the lowest experimentally achiev-able temperature. ture T c ( µ H ext ) /T c (0) versus the applied in-plane field µ H ext . Here, the T c values ranging below the lowest ex-perimentally accessible temperatures are determined byextrapolation. In order to estimate the upper criticalfield H c2 we fit the data to the empirical dependence µ H c2 ( T ) = µ H c2 ( T = 0) (cid:34) − (cid:18) TT c (cid:19) (cid:35) (1)and find µ H c2 ( T = 0) = (13 . ± .
1) T, which agreeswell to the value of µ H c2 = 14 T reported in Ref. 25for TaN films grown on sapphire substrates. This resultshows that our TaN films are sufficiently resilient toexternal magnetic fields in the 1 T-range, required forbbFMR experiments. C. BbFMR experiments and inductive analysis onTaN/Py-bilayers
To investigate the spin transport properties of TaNin the normal and superconducting state, we studySC/FM bilayers, where the FM is a 5 nm thick Ni Fe (Permalloy, Py) thin film. In the following we presentresults on two bilayers: (i) sample A is a TaN/Pybilayer, where the TaN layer is grown using the optimaldeposition parameters (N /Ar=0.35, T depo = 500 ◦ C, p depo = 5 µ bar, P depo = 30 W and d TaN = 60 nm,resulting in T c = 4 . /Ar=0.1, T depo = 500 ◦ C, p depo = 5 µ bar, P depo = 30 W and d TaN = 60 nm) are chosen such that T c < .
25 K.The difference in the growth parameters is the lowerN /Ar gas flow ratio which favors the formation ofTa-rich phases. This is supported by x-ray reflectometryand the extracted D V values shown in Fig. S4 of theSM . Sample B can therefore viewed as a referencesample allowing us to verify whether the experimentallyobserved signatures can be assigned to the formationof a superconducting phase in the TaN. To access the h rf C P W x yz Port 1 H P y T a N d N M d F M m y Port 2 ∂ t MH eff CPWPyTaN J s m x yz (a) (b) H iSHE J qiSHE Figure 3. (a) Sketch of the experimental bbFMR setup in-cluding the measurement geometry for in-plane bbFMR. (b)Schematic illustration for the generation of the charge currentdensity J iSHEq by the ac iSHE. The ac flux H iSHE generatedby J iSHEq is coupled into the coplanar waveguide (CPW). magnetic properties and the spin current phenomena,we perform bbFMR measurements in a cryogenic en-vironment over a broad temperature range. A sketchof the measurement setup and geometry is shown inFig. 3(a). The bilayers are mounted face-down onto acoplanar waveguide (CPW) and we record the complexmicrowave transmission parameter S using a vectornetwork analyzer (VNA). In particular, we measurethe transmission S for fixed microwave frequencies f in the range (5 GHz ≤ f ≤
35 GHz) as a functionof the external magnetic field H ext , applied along the x -direction. We use a sufficiently small VNA microwaveoutput power of 1 mW , such that all spin dynamicsare in the linear regime. For T > T c , the magnetizationdynamics excited in the Py pumps a spin current density J s into the adjacent TaN layer as illustrated in Fig 3(b).In the TaN layer, J s is absorbed and converted intoa charge current J iSHEq via the inverse spin Hall effect(iSHE). On the one hand, the spin pumping effect man-ifests itself as an additional contribution to the Gilbertdamping α of the FMR as it represents an additionalrelaxation channel for angular momentum . On theother hand, the ac magnetic field H iSHE generated viathe iSHE induced ac charge current J iSHEq is inductivelycoupled to the CPW and is detected by the VNA . Allexperiments are performed with H ext (cid:107) x to suppressthe formation of superconducting vortices.We extract the magnetization dynamics parameters bystudying the resonance field µ H res and linewidth µ ∆ H as a function of excitation frequency f . The resonancefield µ H res ( f ) is fitted to the ip-Kittel equation (Eq.(S1) in the SM ) to extract the effective magnetization µ M eff , g -factor and in-plane anisotropy field µ H ani .The frequency evolution of the FMR linewidth µ ∆ H ( f )is fitted with the linear model to extract the Gilbertdamping parameter α and the inhomogeneous broaden-ing µ H inh32 . In this work, we are primarily interestedin the temperature dependence of the Gilbert damping α ( T ) as it is sensitive to spin pumping across the inter-face α = α + α SP , where α is the intrinsic dampingand α SP denotes the additional dissipation channelfor angular momentum via spin pumping . Forcompleteness, we present the temperature dependence ofthe remaining characteristic parameters describing theFMR in section V of the SM . The extracted Gilbert
89 1 . 01 . 1 1 0 1 0 0011 0 1 0 0- 101 a (10-3) A : S C T a N / P y B : N C T a N / P y ( a )( c ) ( b )( d ) A : s = 1 . 1 0 · / W m B : s = 1 . 4 8 · / W m s / s s f/ s T ( K ) s d/ s T ( K ) Figure 4. (a) Temperature dependence of the Gilbert damp-ing parameter α for both the SC (black, A) and NC (red, B)TaN/Py-bilayer. The apparent decrease of α in the SC stateis due to the suppression of spin pumping into the SC dueto the freeze-out of thermally excited quasiparticles. (b) Nor-malized conductivity σ/σ of both samples as a functionof T . A small valley in σ/σ for sample A in the range( T c ≤ T ≤
50 K) mirrors the increase in α . (c) Damping-likeiSOT conductivity σ d normalized by the sample conductanceat T = 300 K σ as a function of T . A positive σ d is de-tected in both samples at high temperatures. In the SC state,the σ d of sample A decays to negative values. (d) Field-likeiSOT conductivity σ f as a function of T . We observe a smallpositive σ f for both samples in the normal state attributed tothe iREE. In the SC state, σ f rises to large positive values.These results are in good agreement to previous results onNbN/Py-bilayers . damping α in Fig. 4(a) is very similar for both samplesand, moreover, is in agreement to a previous study onPy films capped with a thin insulating TaN-layer . Theobserved reduction in α ( T ) with decreasing T down to T = 100 K in both samples is compatible with previousresults obtained for Py thin films . For sample A,we observe an increase in α from 100 K to 5 K, whileTaN is in the NC state. This feature is mirrored in thenormalized conductivity σ/σ of sample A, which wasmeasured via dc resistance experiments and is plotted asa function of T in Fig. 4(b). In sample B, both α ( T ) and σ ( T ) /σ remain roughly constant in this temperaturerange. We hence interpret the increase in α ( T ) in sampleA to an additional resistivity-like damping contributionof this TaN/Py-bilayer . In the SC state, the α ofsample A decreases towards lower temperatures at firstgradually and then at T = 2 . α = 8 . · − . In comparison, the α value of sample B remains roughly constant in thistemperature range. The temperature dependence of α for sample A below T c is attributed to the blockingof spin currents at the TaN/Py-interface, which is inagreement with previous results . For temperaturesslightly below T c , thermally excited quasiparticles inthe SC can still mediate spin currents. Hence, weobserve a gradual reduction of α with decreasing T .The higher σ in Fig. 4(b) for sample B containingTaN grown at a lower N / Ar-ratio agrees with previousresults , and is most likely caused by the higherconcentration of Ta-rich phases in the thin film.By measuring both the FMR amplitude A and phase φ ,we are able simultaneously extract the inverse spin-orbittorque conductivities σ SOT with the data analysisprocedure established in Ref. 32. Exemplary raw datafor the normalized inductive coupling ˜ L between sampleand CPW, which is the fundamental quantity thatrelates the FMR amplitude A and phase φ to the σ SOT ,is shown in the SM section VI . In Fig. 4(c), we plotthe extracted damping-like iSOT σ d for both samplesnormalized by σ . We observe a sizable positive σ d for both samples in the normal state that is abouttemperature independent. This contribution comprisesthe combined iSHE effects of Permalloy and TaN in oursamples. We have previously observed similar positive σ d for NbN/Py-bilayers despite the negative spin Hallangle (SHA) in NbN . Hence, we assume that thecontribution of Py to σ d dominates due to a higher σ ofPy and we can not quantify the magnitude of the SHAof TaN. However, we can state that the various TaNphases exhibit different SHA as evident from the larger σ d of sample B containing primarily Ta-rich phases likeTa N. In the superconducting regime of sample A, σ d first decreases towards zero with decreasing temperaturedue to a superconducting shunting effect of the TaNlayer as previously detected in Ref. . Reducing thetemperature further, it takes increasing negative valuesin agreement with the quasiparticle mediated inversespin Hall effect (QMiSHE) assuming a negative SHAof TaN, like pure Ta . We attribute the abruptmanifestation of negative σ d for T ≤ . . In previous studies, ithas been shown, that proximity to a FM material canhave a significant effect on the superconducting T c56–58 .For (2 . < T < T c ), we thus assume that sample Adoes not exhibit a direct SC/FM-contact and thereforeonly observe the SC shunting effect of the iSHE. Forlower T , the entire TaN layer becomes superconductingand the established direct SC/FM-contact enables theSC quasiparticles to contribute to the spin transport viathe QMiSHE. It is important to note that in the SCstate a diverging spin Hall angle resulting from intrinsicand side-jump contributions to the SHE compensatesthe diminishing quasiparticle population with decreasing T . Similarly, the complete suppression of spinpumping in α in Fig. 4(a) also first manifests below T ≤ . σ d = − (1 . ± . × / Ωm at
T /T c ≈ . σ f normal-ized by σ . We observe small positive values in thenormal state that are compatible with the iREE ,as the Faraday effect would give rise to negative σ f 33 .Similar σ f values have already been detected in Pt/Py-bilayers . In the SC state, we observe a large positive σ f . The observation of a field-like σ f in the SC stateis in agreement with our previous results on NbN/Py-heterostructures . We note that the steep, step-wiseincrease in σ f below 2.5 K provides further evidencefor the presence of a second superconducting transitionfor T ≤ . . From this result, we infer thatthe magnitude of σ f depends on the superconductingcondensate density n s . The derived magnitude for σ f in TaN/Py-bilayers ( σ f = +(1 . ± . × / Ωm at
T /T c ≈ .
5) is lower than that of NbN/Py-bilayers atcomparable reduced temperatures
T /T c . The origin ofthe positive σ f in the SC state is as of today unexplained.Potential sources may be the coherent motion of vorticesin an rf-field , the impact of Meißner screeningcurrents on the magnetization dynamics due to tripletsuperconductivity or non equilibrium effects . Finallywe note that abrupt changes in our σ SOT as function of T enable the indirect detection of additional fractionalsuperconducting transitions in SC/FM-heterostructuresand thereby to study the SC/FM-proximity effect andthin film homogeneity. IV. SUMMARY
In summary, by optimizing the reactive dc magnetronsputtering deposition for superconducting TaN films onSiO , we achieved films with a superconducting T c of upto 5 K and a critical field of µ H c2 ( T = 0) = (13 . ± . α decreases due to the freeze-outof thermally excited quasiparticles and a finite QMiSHEmanifests. Overall the results of bbFMR spectroscopyare in good agreement to those in our previous studyon NbN/Py-bilayers and highlight the universality ofthe observed effects for hard type II s-wave supercon-ductors. Our study demonstrates that TaN is a promis-ing high spin-orbit coupling material for superconduct-ing spintronics. This paves the way towards the studyof a manifold of recently proposed exotic phenomena atthe SC/FM-interface such as the generation of supercur-rents by Rashba spin-orbit interaction , supercurrent-induced spin-orbit torques or the vortex spin Halleffect . SUPPLEMENTARY MATERIAL
See the supplementary material for additional detailson the growth parameters, supporting bbFMR data anddetails on the inductive analysis method
ACKNOWLEDGMENTS
We acknowledge financial support by the DeutscheForschungsgemeinschaft (DFG, German Research Foun-dation) via WE5386/4-1 and Germany’s ExcellenceStrategy EXC-2111-390814868.
DATA AVAILABILITY
The data that support the findings of this study areavailable from the corresponding author upon reasonablerequest.
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