We report on the fabrication and characterization of superconducting magnesium diboride (MgB2) thin films intended for quantum-limited devices based on non-linear kinetic inductance (NLKI) such as parametric amplifiers with either elevated operating temperatures or expanded frequency ranges. In order to characterize the MgB2 material properties, we have fabricated coplanar waveguide (CPW) transmission lines and microwave resonators using 40 nm thick MgB2 films with a measured kinetic inductance of 5.5 pH/ and internal quality factors Qi3×104 at 4.2 K. We measure the NLKI in MgB2 by applying a DC bias to a 6 cm long by 4 μm wide CPW transmission line and measuring the resulting phase delay caused by the current dependent NLKI. We also measure the current dependent NLKI through CPW resonators that shift down in frequency with increased power applied through the CPW feedline. Using these measurements, we calculate the characteristic non-linear current parameter, I*, for multiple CPW geometries. We find values for corresponding current density, J*=1222 MA/cm2, and a ratio of the critical current to the non-linear current parameter, IC/I*=0.140.26, similar to or higher than values for other superconductors such as NbTiN and TiN.

1.
P. K.
Day
,
H. G.
LeDuc
,
B. A.
Mazin
,
A.
Vayonakis
, and
J.
Zmuidzinas
, “
A broadband superconducting detector suitable for use in large arrays
,”
Nature
425
(
6960
),
817
821
(
2003
).
2.
J.
Zmuidzinas
, “
Superconducting microresonators: Physics and applications
,”
Annu. Rev. Condens. Matter Phys.
3
,
169
214
(
2012
).
3.
A.
Sergeev
,
V.
Mitin
, and
B.
Karasik
, “
Ultrasensitive hot-electron kinetic-inductance detectors operating well below the superconducting transition
,”
Appl. Phys. Lett.
80
(
5
),
817
819
(
2002
).
4.
S.
Doyle
,
P.
Mauskopf
,
J.
Naylon
,
A.
Porch
, and
C.
Duncombe
, “
Lumped element kinetic inductance detectors
,”
J. Low Temp. Phys.
151
,
530
536
(
2008
).
5.
J.
Perido
,
P.
Day
,
A.
Beyer
,
N. F.
Cothard
,
S.
Hailey-Dunsheath
,
H.
Leduc
,
B. H.
Eom
, and
J.
Glen
, “
Parallel plate capacitor aluminum kids for future far-infrared space-based observatories
,”
J. Low Temp. Phys.
214
(
3
),
200
209
(
2024
).
6.
B. A.
Mazin
, “
Microwave kinetic inductance detectors: The first decade
,”
AIP Conf. Proc.
1185
,
135
142
(
2009
).
7.
M. R.
Vissers
,
J. E.
Austermann
,
M.
Malnou
,
C. M.
McKenney
,
B.
Dober
,
J.
Hubmayr
,
G. C.
Hilton
,
J. N.
Ullom
, and
J.
Gao
, “
Ultrastable millimeter-wave kinetic inductance detectors
,”
Appl. Phys. Lett.
116
,
032601
(
2020
).
8.
B.
Ho Eom
,
P. K.
Day
,
H. G.
LeDuc
, and
J.
Zmuidzinas
, “
A wideband, low-noise superconducting amplifier with high dynamic range
,”
Nat. Phys.
8
(
8
),
623
627
(
2012
).
9.
F.
Faramarzi
,
R.
Stephenson
,
S.
Sypkens
,
B. H.
Eom
,
H.
LeDuc
, and
P.
Day
, “
A 4–8 GHz kinetic inductance traveling-wave parametric amplifier using four-wave mixing with near quantum-limited noise performance
,”
APL Quantum
1
,
036107
(
2024
).
10.
S.
Shu
,
N.
Klimovich
,
B. H.
Eom
,
A.
Beyer
,
R. B.
Thakur
,
H.
Leduc
, and
P.
Day
, “
Nonlinearity and wide-band parametric amplification in a (Nb, Ti) N microstrip transmission line
,”
Phys. Rev. Res.
3
(
2
),
023184
(
2021
).
11.
M.
Malnou
,
M.
Vissers
,
J.
Wheeler
,
J.
Aumentado
,
J.
Hubmayr
,
J.
Ullom
, and
J.
Gao
, “
Three-wave mixing kinetic inductance traveling-wave amplifier with near-quantum-limited noise performance
,”
PRX Quantum
2
(
1
),
010302
(
2021
).
12.
D.
Cunnane
,
H.
Leduc
,
N.
Klimovich
,
F.
Faramarzi
,
A.
Beyer
, and
P.
Day
, “
High-efficiency Ka-band frequency multiplier based on the non-linear kinetic inductance in a superconducting microstrip
,”
Appl. Phys. Lett.
124
,
022601
(
2024
).
13.
A.
Kher
,
P. K.
Day
,
B. H.
Eom
,
J.
Zmuidzinas
, and
H. G.
Leduc
, “
Kinetic inductance parametric up-converter
,”
J. Low Temp. Phys.
184
,
480
485
(
2016
).
14.
S.
Sypkens
,
F.
Faramarzi
,
M.
Colangelo
,
A.
Sinclair
,
R.
Stephenson
,
J.
Glasby
,
P.
Day
,
K.
Berggren
, and
P.
Mauskopf
, “
Development of an array of kinetic inductance magnetometers (KIMs)
,”
IEEE Trans. Appl. Supercond.
31
(
5
),
1
4
(
2021
).
15.
F.
Faramarzi
,
S.
Sypkens
,
R.
Stephenson
,
B. H.
Eom
,
H.
Leduc
,
S.
Chaudhuri
, and
P.
Day
, “
A near quantum limited sub-GHz TiN kinetic inductance traveling wave parametric amplifier operating in a frequency translating mode
,” arXiv:2406.00530 (
2024
).
16.
J.
Aumentado
, “
Superconducting parametric amplifiers: The state of the art in Josephson parametric amplifiers
,”
IEEE Microwave Mag.
21
(
8
),
45
59
(
2020
).
17.
C.
Macklin
,
K.
O'brien
,
D.
Hover
,
M.
Schwartz
,
V.
Bolkhovsky
,
X.
Zhang
,
W.
Oliver
, and
I.
Siddiqi
, “
A near–quantum-limited josephson traveling-wave parametric amplifier
,”
Science
350
(
6258
),
307
310
(
2015
).
18.
P.
Szypryt
,
D. A.
Bennett
,
I. F.
Florang
,
J. W.
Fowler
,
A.
Giachero
,
R.
Hummatov
,
A. E.
Lita
,
J. A. B.
Mates
,
S. W.
Nam
,
G. C.
O'Neil
,
D. S.
Swetz
,
J. N.
Ullom
,
M. R.
Vissers
,
J.
Wheeler
, and
J.
Gao
, “
Kinetic inductance current sensor for visible to near-infrared wavelength transition-edge sensor readout
,”
Commun. Eng.
3
,
160
(
2024
).
19.
C.
Kim
,
C.
Bell
,
J. M.
Evans
,
J.
Greenfield
,
E.
Batson
,
K. K.
Berggren
,
N. S.
Lewis
, and
D. P.
Cunnane
, “
Wafer-scale magnesium diboride thin films with tunable high kinetic inductance
,”
ACS Nano
18
(
40
),
27782
27792
(
2024
).
20.
H.
Kim
,
K.
Cho
,
M. A.
Tanatar
,
V.
Taufour
,
S. K.
Kim
,
S. L.
Bud'ko
,
P. C.
Canfield
,
V. G.
Kogan
, and
R.
Prozorov
, “
Self-consistent two-gap description of mgb2 superconductor
,”
Symmetry
11
(
8
),
1012
(
2019
).
21.
F. W.
Carter
,
T. S.
Khaire
,
V.
Novosad
, and
C. L.
Chang
, “
scraps: An open-source python-based analysis package for analyzing and plotting superconducting resonator data
,”
IEEE Trans. Appl. Supercond.
27
,
1
5
(
2017
).
22.
A.
Arsenovic
,
J.
Hillairet
,
J.
Anderson
,
H.
Forstén
,
V.
Rieß
,
M.
Eller
,
N.
Sauber
,
R.
Weikle
,
W.
Barnhart
, and
F.
Forstmayr
, “
scikit-rf: An open source python package for microwave network creation, analysis, and calibration [speaker's corner]
,”
IEEE Microwave Mag.
23
(
1
),
98
105
(
2022
).
23.
D. M.
Pozar
,
Microwave Engineering
, 3rd ed. (
Wiley
,
Hoboken, NJ
,
2005
).
24.
L. J.
Swenson
,
P. K.
Day
,
B. H.
Eom
,
H. G.
Leduc
,
N.
Llombart
,
C. M.
McKenney
,
O.
Noroozian
, and
J.
Zmuidzinas
, “
Operation of a titanium nitride superconducting microresonator detector in the nonlinear regime
,” arXiv:13054281v1 (
2013
).
25.
S.
Probst
,
F. B.
Song
,
P. A.
Bushev
,
A. V.
Ustinov
, and
M.
Weides
, “
Efficient and robust analysis of complex scattering data under noise in microwave resonators
,” arXiv:14103365v2 (
2014
).
26.
X.
Dai
,
X.
Liu
,
Q.
He
,
Y.
Chen
,
Z.
Mai
,
Z.
Shi
,
W.
Guo
,
Y.
Wang
,
M. R.
Vissers
, and
J.
Gao
, “
New method for fitting complex resonance curve to study nonlinear superconducting resonators
,”
Supercond. Sci. Technol.
36
(
1
),
015003
(
2023
).
27.
M.
Vissers
,
M.
Sandberg
,
T.
Ohki
,
J.
Kline
,
M.
Weides
,
J.
Gao
, and
D.
Pappas
, “
Frequency-tunable superconducting resonators via nonlinear kinetic inductance
,”
Appl. Phys. Lett.
107
(
6
),
062601
(
2015
).
You do not currently have access to this content.