# David S Wisbey, Ph.D.

Assistant Professor
Physics

## Education

Postdoctoral Fellowship
NIST, Boulder, CO 2008-2011
Education
- Ph.D., Condensed Matter Physics,
- M.S., Physics, Univ. of Nebraska-Lincoln 2005
- B.A., Physics, Union College, Lincoln, NE 2002

## Research Interests

Wisbey's research interests include materials for quantum computing, microwave resonators and amplifiers, and neutron detectors. Currently, he uses coplanar waveguides as a tool to probe different materials including defects in Si(100), boron nitride, and graphene. Noise in electronics is a fundamental issue that occurs in many different areas including 2D materials and superconducting circuits. Decoherence is generated by materials which quantum bits are made of, this is a major obstacle preventing a working quantum computer. His background in surface science is an invaluable tool he uses to address important questions about materials used in quantum computing.

## Labs and Facilities

The 3-Port Simulation Method File for Sonnet:

The following curve equation file can be inserted into Sonnet to calculate the local
as:

FTYP EQUA 4! Sonnet Equations File

EQN “QZin3”
EQS USER FILE
EQD Calculate Q factor from input impedance of port3. EQH
Zin3=Z03*(1+s33)/(1-s33)
Q=f0/2*slope of imag(Zin3)/real(Zin3)
END EQH
AXISLABEL “Q”
ARGS 1
ARG 1!begin arg 1 definition
NAME s33
RES S 33
END ARG ! end of arg 1 definition
BODY
0.5*FREQ[f]*(imag(50*(1+s33[f])/(1-s33[f])) - imag(50*(1+s33[f-1])/(1-s33[f-1]))/(FREQ[f]-FREQ[f-1]) /real(50*(1+s33[f])/(1-s33[f]))
END BODY
END EQN

## Publications and Media Placements

Presentations

Using Superconducting Microwave Resonators to Measure the Dielectric Constant and Quality Factor of Ortho-Carborane-Capped Aluminum Nanoparticle Thin Films,  Jacob Brewster, Xander Benziger, Paul Jelliss, David Wisbey, APS March Meeting, New Orleans, 2017.

Publications

D. S. Wisbey, A. Martin, A. Reinisch, "New Method for Determining the Quality Factor and Resonance Frequency of Superconducting Micro-Resonators from Sonnet Simulations"
J. Low Temp. Phys. 176, 538-544, (2014).

M. R. Vissers, J. Gao, J. S. Kline, M. O. Sandberg, M. P. Weides, D. S. Wisbey, D. P. Pappas, "Characterization and in-situ monitoring of sub-stoichiometric adjustable superconducting critical temperature titanium nitride growth", Thin Solid Films 548, 485 (2013).

M. R. Vissers, J. Gao, M. O. Sandberg, S. M. Duff, D. S. Wisbey, K. D. Irwin, D. P. Pappas, "Proximity-coupled Ti/TiN multilayers for use in kinetic inductance detectors" Appl. Phys. Lett. 102, 23, 232603 (2013).

J. Gao, M. R. Vissers, M. O. Sandberg, F. C. S. da Silva, S. W. Nam, D. P. Pappas, D. S. Wisbey, E. C. Langman, S. R. Meeker, B. A. Mazin, H. G. Leduc, J. Zmuidzinas, K. D. Irwin, "A titanium-nitride near-infrared kinetic inductance photon-counting detector and it anomalous electrodynamics", Appl. Phys. Lett. 101, 142602, (2012).

M. Sandberg, M. R. Vissers, J. S. Kline, M. Weides, J. S. Gao, D. S. Wisbey, D. P. Pappas, "Etch induced microwave lasses in titanium nitride superconducting resonators", Appl. Phys. Lett. 100, 26, 262605 (2012).

M. R. Vissers, J. S. Kline, J. S. Gao, D. S. Wisbey, D. P. Pappas, "Reduced microwave loss in trenched superconducting coplanar waveguides", Appl. Phys. Lett. 100, 082602 (2012).

J. S. Kline, M. R. Vissers, F. C. S. da Silva, D. S. Wisbey, M. Weides, t. J. Weir, B. Turek, D. A. Braje, W. D. Oliver, Y. Shalibo, N. Katz, B.R. Johnson, T. A. Ohki, D. P. Pappas, "Sub-micrometer epitaxial Josephson junctions for quantum circuits.", Superconduc. Sci. Tech. 25, 025005 (2012).

M. P. Weides, J. S. Kline, 1 M. R. Vissers, M. O. Sandberg, D. S. Wisbey, B. R. Johnson, T. A. Ohki, D. P . Pappas, "Coherence in transmon qubit with epitaxial tunnel junctions", Appl. Phys. Lett. 99, 262502 (2011).
D. P. Pappas, M. R. Vissers, D. S. Wisbey, J. S. Kline, J. S. Gao, "Two Level System Loss in Superconducting Microwave Resonators", IEEE Trans. Appl. Supercond. 21, 871 (2011).

M. R. Vissers, J. Gao, D. S. Wisbey, D. A. Hite, C. C. Tsuei, A. D. Corcoles, M. Steffen, D. P. Pappas, "Low Loss Superconducting Titanium Nitride Coplanar Waveguide Resonators", Appl. Phys. Lett. 97, 232509 (2010).

D. S. Wisbey, J. Gao, M. R. Vissers, F. C. S. Da Silva, J. S. Kline, L. Vale, D. P. Pappas, "Effect of metal/substrate interfaces on RF loss in superconducting coplanar waveguides", J. Appl. Phys. 108, 093918 (2010)

L. Yuan, D. S. Wisbey, S. T. Halloran, D. P. Pappas, F. C. S. da Silva, H. Z. Fardi, "Magnetization scissoring in aluminum/Permalloy microstructures", J. Appl. Phys. 106, 113919 (2009)

David S. Wisbey, N. Wu, D. Feng, A. N. Caruso, J. Belot, Ya. B. Losovyj, E. Vescovo, P. A. Dowben, "Induced Spin Polarization of Copper Spin ½ Molecular Layers", Phys. Lett.
A, 373, 484 (2009)

David Wisbey, N. Wu, Y. Losovyj, I. Ketsmana, A. N. Carusoc, D. Feng, J. Belot, Elio Vescovo, P. A. Dowben, "Radiation Induced Decomposition of the Metal-Organic Molecule Bis(4-cyano- 2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II)", Appl. Surf. Sci. 255, 3576 (2009)

David Wisbey, N. Wu, D. Feng, A. N. Caruso, J. Belot, Y. Losovyj, E. Vescovo, P. A. Dowben, "Interface-Induced Spin Dipole Ordering of the Copper Spin 1/2 Molecule: Bis(4-cyano-2,2,6,6-tetramethyl-3,5-heptanedionato)copper(II)" J. Phys. Chem. C 112, 13656 (2008)

N. Wu, R.F. Sabirianov, C.-G. Duan, W. N. Mei, David Wisbey, Ya. B. Losovyj, M. Manno, C. Leighton, En Cai, J. Zhang, P. A. Dowben, "The Surface Stability of CoS2(100)", J. Phys: Condens. Matter 20, 215231 (2008)

N. Wu, David Wisbey, T. Komesu, Z.X. Yu, M. Manno, L. Wang, C. Leighton, P.A. Dowben, "The kinetic energy dependent effective Debye temperature for CoS2 (100)", Phys. Lett. A, 372, 2484 (2008)

David Wisbey, D. Feng, M.T. Bremer, C.N. Borca, A.N. Caruso, C.M. Silvernail, J. Belot, E. Vescovo, "Electronic Structure of a Metal-Organic Copper Spin-1/2 Bis(4- cyano-2,2,6,6- tetramethyl-3,5-heptanedionato)copper(II)", J. Am. Chem. Soc. 129, 6249 (2007)

Z.X. Yu, M.A. Van Hove, S.Y. Tong, David Wisbey, Ya.B. Losovyj, N. Wu, M. Manno, L. Wang, C. Leighton, W.N. Mei, P.A. Dowben, "The structure of the CoS2(100)-(1X1) surface", J. Phys.: Condens. Matter 19, 156223 (2007)

N. Wu, Ya.B. Losovyj, David Wisbey, K. Belashchenko, M. Manno, L. Wang, C. Leighton, P.A. Dowben, "The Electronic Band Structure CoS2", J. Phys.: Condens. Matter 19, 156224 (2007)

D.Q. Feng, David Wisbey, Ya.B. Losovyj, Y. Tai, M. Zharnikov, P.A. Dowben, "Electronic structure and polymerization of a self-assembled monolayer with multiple arene rings", Phys. Rev. B 74, 165425 (2006)

D.Q. Feng, David Wisbey, Y. Tai, Ya.B. Losovyj, M. Zharnikov, P.A. Dowben, "Abnormal Temperature Dependence of Photoemission Intensity Mediated by Thermally Driven Reorientation of a Monomolecular Film", J. Phys. Chem. B 110, 1095 (2006)

H.-J. Jeong, R. Skomski, David Wisbey, P.A. Dowben, "Magnon-plasmon interactions", Phys. Lett. A 341, 508 (2005)

Ya.B. Losovyj, I.N. Yakovkin, H.-J. Jeong, David Wisbey, P.A. Dowben, "Lattice stiffening transition in gadolinium chains in furrowed (112) surfaces", J. Phys.: Condens. Matter 16, 4711 (2004).

Ya.B. Losovyj, David Wisbey, P.A. Dowben, "The photoemission from the gadolinium submonolayers on W(112)", Synchrotron Radiation in Natural Science 3, N1-2, 76 (2004).