Intrinsic nonlinearity probed by intermodulation distortion microwave measurements on high quality MgB2 thin films

Cifariello, G.; Aurino, Mario; Gennaro, Emiliano Di; Lamura, G.; Andreone, A.; Orgiani, P.; Xi, X. X.; Villégier, Jean-Claude

doi:10.1063/1.2193053

Cited by 14 publications

(14 citation statements)

References 17 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It should also be mentioned that Dahm and Scalapino [9] have calculated IMD that is close in value to that in YBCO. These elevated IMD results are consistent with recently reported measurements on films of comparable quality [10].…”

Section: Intermodulation Distortionsupporting

confidence: 94%

Intermodulation Distortion and Nonlinearity in ${\rm MgB}_{2}$: Experiment and Theory

Oates

Agassi

Moeckly

2007

IEEE Trans. Appl. Supercond.

View full text Add to dashboard Cite

The nonlinear surface impedance and intermodulation distortion (IMD) products of MgB 2 thin films have been measured as a function of temperature. The measurements use a stripline-resonator technique, following an approach that was developed and extensively applied to similar measurements of YBCO. The films were grown using the deposition technique of reactive evaporation onto LaAlO 3 and sapphire substrates. The low-power ( ) is comparable to that of sputtered Nb films on sapphire, and lower than that of YBCO at the corresponding reduced temperatures. The rf-magnetic-field dependence at 20 K follows a moderate slope for rf 500 Oe. At higher rf magnetic fields the increase is larger. The IMD values are larger than those of the best quality YBCO by more than 10 dB. The theoretical analysis assumes uncoupled and channels (no interband scattering) and intrinsic nonlinearity to the lowest nonlinear order in the radiation field. Under these assumptions, the calculated IMD indicates dominance of the -channel contribution in the clean limit, with a temperature dependence that is consistent with the measured curve. This result indicates that the observed IMD may be consistent with an intrinsic origin for the nonlinearity.

show abstract

Section: Intermodulation Distortionsupporting

confidence: 94%

Intermodulation Distortion and Nonlinearity in ${\rm MgB}_{2}$: Experiment and Theory

Oates

Agassi

Moeckly

2007

IEEE Trans. Appl. Supercond.

View full text Add to dashboard Cite

show abstract

“…Recently there has been an emerging interest in microwave response of MgB 2 [107,108,109] and a possibility of using MgB 2 in resonant cavities for particle accelerators [110,111]. These issues require understanding nonlinear electrodynamics and current pairbreaking in two-gap superconductors [112,113], in particular, band decoupling and the formation of interband phase textures at strong rf currents [16,17].…”

Section: Discussionmentioning

confidence: 99%

Limits of the upper critical field in dirty two-gap superconductors

Gurevich

2007

Physica C: Superconductivity

175

189

View full text Add to dashboard Cite

An overview of the theory of the upper critical field in dirty two-gap superconductors, with a particular emphasis on MgB2 is given. We focus here on the maximum Hc2 which may be achieved by increasing intraband scattering, and on the limitations imposed by weak interband scattering and paramagnetic effects. In particular, we discuss recent experiments which have recently demonstrated ten-fold increase of Hc2 in dirty carbon-doped films as compared to single crystals, so that the Hc2(0) parallel to the ab planes may approach the BCS paramagnetic limit, Hp[T ] = 1.84Tc[K] ≃ 60 − 70T . New effects produced by weak interband scattering in the two-gap Ginzburg-Landau equations and Hc2(T ) in ultrathin MgB2 films are addressed.

show abstract

“…According to Collings et al [5], MgB 2 -coated cavities can potentially exhibit a higher superheating critical field H sh than that of Nb, and as a result, a much higher E acc would be imaginable [10]. In addition, MgB 2 exhibits a low surface resistance (R S ) [11][12][13][14] and is free from the weak link behavior that is encountered in high T c superconductors [15][16][17][18][19][20], implying better power dependence of R S [21]. While the issue has been raised that H c1 could be a limiting factor for MgB 2 since its bulk H c1 value is lower than that of Nb, studies suggest that it can be enhanced through the employment of multilayer structures containing superconductive films thinner than the London penetration depth, placed between insulating layers [22].…”

Section: Introductionmentioning

confidence: 99%

Superconducting magnesium diboride coatings for radio frequency cavities fabricated by hybrid physical-chemical vapor deposition

Wolak

Tan

Krick

et al. 2014

Phys. Rev. ST Accel. Beams

View full text Add to dashboard Cite

We have investigated the coating of an inner surface of superconducting radio frequency cavities with a magnesium diboride thin film by hybrid physical-chemical vapor deposition (HPCVD). To simulate a 6 GHz rf cavity, a straight stainless steel tube of 1.5-inch inner diameter and a dummy stainless steel cavity were employed, on which small sapphire and metal substrates were mounted at different locations. The MgB 2 films on these substrates showed uniformly good superconducting properties including T c of 37-40 K, residual resistivity ratio of up to 14, and root-mean-square roughness R q of 20-30 nm. This work demonstrates the feasibility of coating the interior of cylindrical and curved objects with MgB 2 by the HPCVD technique, an important step towards superconducting rf cavities with MgB 2 coating.

show abstract

Intrinsic nonlinearity probed by intermodulation distortion microwave measurements on high quality MgB2 thin films

Cited by 14 publications

References 17 publications

Intermodulation Distortion and Nonlinearity in ${\rm MgB}_{2}$: Experiment and Theory

Intermodulation Distortion and Nonlinearity in ${\rm MgB}_{2}$: Experiment and Theory

Limits of the upper critical field in dirty two-gap superconductors

Superconducting magnesium diboride coatings for radio frequency cavities fabricated by hybrid physical-chemical vapor deposition

Contact Info

Product

Resources

About