Guoxing Miao

Professor, Electrical and Computer Engineering

Research interests: spintronics for information processing; nanodevices based on new spin systems such as topological insulators; synthetic diamonds

Biography

Professor Guoxing Miao joined the ECE Department in September 2012. He received his BSc from Shandong University, China, in 1999. He then moved to Brown University, USA, and received his MSc in 2003 and PhD in 2006. After graduation, Miao joined Francis Bitter Magnet Laboratory at MIT as a postdoctoral associate, and later on promoted to Research Scientist in 2009. In 2011, he moved to University of Waterloo, Canada, joining the Institute for Quantum Computing (IQC) as Research Assistant Professor in 2011, and the Electrical & Computer Engineering department as Assistant Professor in 2012. He remains cross appointed with both IQC and ECE department.

Miao's research interests lie in spintronics, using precise electron spin manipulation for information processing. His research effort has strong emphasis on nanodevices established on newly emerging spin platforms, such as synthetic diamonds and topological insulators, where information can be processed coherently on the quantum level, rather than digitally on the classical level.

Education

PhD, Physics, Brown University, 2006
MSc, Physics, Brown University, 2003
BSc, Physics, Shandong University, 1999

Guoxing Miao

Research

Professor Guoxing Miao’s research focuses on a specific aspect of the electrons - their spin degrees of freedom. Spin-based nanoelectronic devices offer improved performance and scalability compared to their classical counterparts. As the device dimensions shrink towards nm range and below, quantum information is further harvested from the spin systems which lead to even more powerful information processing capabilities.

Much of the research efforts are devoted to the interplay between different, sometimes incompatible, spin systems. Quantum mechanical tunneling across a sub-nm insulator barrier readily converts a system’s spin information into a well detectable voltage signal. These are known as magnetic tunnel junctions and are widely used in industry as sensitive magnetic sensors and non-volatile data storage elements. Based on the same platform, spin logic devices with much reduced power consumptions are readily achievable by applying unconventional electrode and barrier materials, as well as inducing and manipulating pure spin current flow across controlled channels.

Miao’s research also branches into some of the newly discovered spin systems. Topological insulators, where electrons are strongly correlated into a quantum spin Hall state, are known to host a type of exotic quasiparticles when coupled with superconductors, another condensate of paired electron spins. Such a system is the ideal candidate for realizing quantum computing in a pure solid state fashion because of the innate error tolerance associated with its topological nature. Braiding and detection operations are performed with gated nanobridge structures. Another major project involves diamond single crystals. When carefully doped with nitrogen atoms at selected positions, diamond matrix can create a pair of trapped electrons and form a sub-nm spin system. Such a defect center, known as an NV center, maintains extremely long spin coherence time that is suitable for quantum information processing, and at the same time, exhibits high sensitivity to external magnetic fields therefore also suitable for spin information extraction. By shifting away from conventional optical detection of the NV centers and introducing electrical detections on the system resonance, integration with classical electronics is now made plausible at the cost of certain functionalities. Overall, Miao’s research team place strong emphasis on nanodevice fabrication and advanced materials synthesis, in search for an ideal information platform that will take us to an era beyond silicon.

Research Interests

Spin memory and logic devices, CMOS compatible
Topologically protected 2D spin system
Diamond spintronics with electrical detection

Publications

Recent publications include:

“Observation of tunnel magnetoresistance in a superconducting junction with Zeeman-split energy bands”, B. Li, G.X. Miao, J.S. Moodera, Phys. Rev. B 88(16), 161105(R) (2013)
“Direct evidence of spin filtering across MnFe2O4 tunnel barrier by Meservey-Tedrow experiment”, S. Matzen, J.B. Moussy, G.X. Miao, J.S. Moodera, Phys. Rev. B 87(18), 184422 (2013)
“Superconducting microstrip resonator for pulsed ESR of thin films”, O.W.B. Benningshof, H.R. Mohebbi, I.A.J. Taminiau, G.X. Miao, D.G. Cory, J. Magn. Res. 230, 84 (2013)
“Reduction of the deposition temperature of high quality EuO films on Yttria Stabilized Zirconia by incorporating an MgO buffer layer”, I. Moder, G. Garcia, J. Santiso, J.S. Moodera, G.X. Miao, A.F. Lopeandia, J. Rodriguez-Viejo, Thin Solid Films 531, 466 (2013)
“Magnetic Tunnel Junctions with MgO-EuO composite tunnel barriers”, G.X. Miao, J.S. Moodera, Phys. Rev. B 85, 144424 (2012)
“Interface and Temperature Dependent Magnetic Properties in Permalloy Thin Films and Tunnel Junction Structure”, J.F. Sierra, V.V. Pryadun, S.E. Russek, M. Garcia-Hernandez, F. Mompean, R. Rozada, O. Chubykalo-Fesenko, E. Snoeck, G.X. Miao, J.S. Moodera, F.G. Aliev, J. NanoSci. NanoTech. 11(9), 7653 (2011)
“Domain wall induced magnetoresistance in a superconductor/ferromagnet nanowire”, G.X. Miao, M. Mascaro, C.H. Nam, C.A. Ross, J.S. Moodera, Appl. Phys. Lett. 99(3), 032501 (cover article of issue 18 July 2011)
“Tunneling path toward spintronics”, G.X. Miao, M. Münzenberg, J.S. Moodera, Rep. Prog. Phys. 74, 036501 (2011)
“Spin switch based on double spin-filter tunnel junction geometry”, G.X. Miao, J.S. Moodera, J. Appl. Phys. 108(8), 083910 (2010)
“Understanding tunneling magnetoresistance during thermal annealing in MgO-based junctions with CoFeB electrodes”, W.G. Wang, C. Ni, G.X. Miao, C. Weiland, L.R. Shah, X. Fan, P. Parson, J. Jordan-sweet, X.M. Kou, Y.P. Zhang, R. Stearrett, E.R. Nowak, R. Opila, J.S. Moodera, J.Q. Xiao, Phys. Rev. B 81(14), 144406 (2010)
“Frontiers in spin-polarized tunneling”, J.S. Moodera, G.X. Miao, T.S. Santos, Phys. Today 63(4), 46 (2010)
“In-situ characterization of rapid crystallization of amorphous CoFeB electrodes in CoFeB/MgO/CoFeB junctions during thermal annealing”, W.G. Wang, J. Jordan-sweet, G.X. Miao, C. Ni, A. Rumaiz, L.R. Shah, X. Fan, P. Parson, R. Stearrett, E.R. Nowak, J.S. Moodera, J.Q. Xiao, Appl. Phys. Lett. 95(24), 242501 (2009)
“Growth and Properties of Epitaxial Chromium Dioxide (CrO2) Thin Films and Heterostructures”, G.X. Miao, A. Gupta, Symposium on Nanoscale Magnetic Materials and Applications held at the 2007 MRS Fall Meeting 2007, Boston, MA, chapter in “Nanoscale Magentic Materials and Applications”, 511-536 (2009)
“Exchange splitting and bias-dependent transport in EuO spin filter tunnel barriers”, M. Müller, G.X. Miao, J.S. Moodera, EPL 88(4), 47006 (2009)
“Anomalous bias dependence in magnetic tunnel junctions based on half-metallic CrO2 with heteroepitaxial SnO2 tunnel barrier”, G.X. Miao, G. Xiao, A. Gupta, EPL 87(4), 47006 (2009)
“Numerical evaluations on the asymmetric bias dependence of magnetoresistance in double spin filter tunnel junctions”, G.X. Miao, J.S. Moodera, J. Appl. Phys. 106(2), 023911 (2009)
“Growth of CrO2 coated single crystalline (SnO2) tin oxide nanowires”, S. Budak, G.X. Miao, A. Gupta,IEEE SoutheastCon 2009, Atlanta, GA, Proc. IEEE Tech. Proc. 225-229 (2009)
“Controlling magnetic switching properties of EuS for constructing double spin filter magnetic tunnel junctions”, G.X. Miao, J.S. Moodera, Appl. Phys. Lett. 94(18), 182504 (2009)
“Thickness dependence of ferromagnetic- and metal-insulator transition in thin EuO films”, M. Müller, G.X. Miao, J.S. Moodera, J. Appl. Phys. 105(7), 07C917 (2009)
“Magnetoresistance and its unconventional bias dependence in double spin filter tunnel junctions”, G.X. Miao, M. Müller, J.S. Moodera, Phys. Rev. Lett. 102(7), 076601 (2009) - selected as the "Editor’s Suggestion" in PRL & "Viewpoint" in Physics
“Measuring the spin polarization in half metals by femtosecond spin excitation”, G. Müller, J. Walowski, M. Djordjevic, G.X. Miao, A. Gupta, A.V. Ramos, K. Gehrke, V. Moshnyaga, K. Samwer, J. Schmalhorst, A. Thomas, G. Reiss, J.S. Moodera, M. Münzenberg, Nat. Mater. 8, 56 (2009)
“Epitaxial growth of MgO and Fe/MgO/Fe mgnetic tunnel junctions on (100)-Si by molecular beam epitaxy”, G.X. Miao, J.Y. Chang, M.J. van Veenhuizen, K. Thiel, M. Seibt, G. Eilers, M. Münzenberg, J.S. Moodera, Appl. Phys. Lett.93(14), 142511 (2008)
“Influence of oxidation on the spin filtering properties of CoFe2O4 and the resultant spin polarization”, A.V. Ramos, T.S. Santos, G.X. Miao, M.-J. Guittet, J.-B. Moussy, J.S. Moodera, Phys. Rev. B 78(18), 180402 (2008)
“Infinite magnetoresistance from spin dependent proximity effect in symmetry driven bcc-Fe/V/Fe heteroepitaxial superconducting spin valves”, G.X. Miao, A.V. Ramos, J.S. Moodera, Phys. Rev. Lett. 101(13), 137001 (2008)
“Large spin diffusion length in an amorphous organic semiconductor”, J.H. Shim, K.V. Raman, Y.J. Park, T.S. Santos, G.X. Miao, B. Satpati, and J.S. Moodera, Phys. Rev. Lett.100(22), 226603 (2008)
“Disturbance of tunneling coherence by oxygen vacancy in epitaxial Fe/MgO/Fe magnetic tunnel junctions”, G.X. Miao, Y.J. Park, J.S. Moodera, M. Seibt, G. Eilers, M. Münzenberg, Phys. Rev. Lett. 100(24), 246803 (2008)
“Controlled synthesis and characterization of Ag2S films with varied microstructures and its role as asymmetric barrier layer in trilayer junctions with dissimilar electrodes”, I.C. Lekshmi, G. Berera, Y. Afsar, G.X. Miao, T. Nagahama, T. Santos, J.S. Moodera, J. Appl. Phys. 103(9), 093719 (2008)
“Activation of additional energy dissipation processes in the magnetization dynamics of epitaxial chromium dioxide films”, G.M. Müller, M. Münzenberg, G.X. Miao, A. Gupta,Phys. Rev. B 77(2), 020412(R) (2008)
“Structural and magnetic properties of self-assembled nickel nanoparticles in a yttria stabilized zirconia matrix”, J.T. Abiade, G.X. Miao, A. Gupta, A.A. Gapud, D. Kumar, Thin Solid Films 516(8), 2082 (2008)
“Are the surfaces of CrO2 metallic?”, C.A. Ventrice, D.R. Borst, H. Geisler, J. van Ek, Y.B. Losovyj, P.S. Robbert, U. Diebold, J.A. Rodriguez, G.X. Miao, A. Gupta, J. Phys. Cond. Matter. 19(31), 315207 (2007)
“Influence of spin-polarized current on superconductivity and the realization of large magnetoresistance”, G.X. Miao, K. Yoon, T.S. Santos, J.S. Moodera, Phys. Rev. Lett.98(26), 267001 (2007)
“Planar Hall effect and magnetic anisotropy in epitaxially strained chromium dioxide thin films”, S.T.B. Goennenwein, R.S. Keizer, S.W. Schink, I. Van Dijk, T.M. Klapwijk, G.X. Miao, G. Xiao, A. Gupta, Appl. Phys. Lett.90(14), 142509 (2007)
“Tunneling magnetoresistance observed in La0.67Sr0.33MnO3/organic molecule/Co junctions”, W. Xu, G.J. Szulczewski, P. LeClair, I. Navarrete, R. Schad, G.X. Miao, H. Guo, A. Gupta, Appl. Phys. Lett. 97(7), 072506 (2007)
“Synthesis and magnetic properties of FePt nanoparticles with hard nonmagnetic shells”, S.S. Kang, S. Shi, G.X. Miao, Z.Y. Jia, D.E. Nikles, J.W. Harrell, J. Nano. Nano. 7(1), 350 (2007)
“Magnetic tunnel junctions based on CrO2/SnO2 epitaxial bilayers”, G.X. Miao, P. LeClair, A. Gupta, G. Xiao, M. Varela, S. Pennycook, Appl. Phys. Lett.89(2), 022511 (2006)
“Ultrafast spin-dynamics in half-metallic CrO2 thin films”, Q. Zhang, A.V. Nurmikko, G.X. Miao, G. Xiao, A. Gupta,Phys. Rev. B 74(6), 064414 (2006)
“Magnetic anisotropy in epitaxial CrO2 and CrO2/Cr2O3 bilayer thin films”, N.A. Frey, S. Srinath, H. Srikanth, M. Varela, S. Pennycook, G.X. Miao, A. Gupta, Phys. Rev. B 74(2), 024420 (2006)
“Influence of substrate treatment on the growth morphology and magnetic anisotropy of epitaxial CrO2 films”, G.X. Miao, G. Xiao, A. Gupta, Phys. Stat. Sol. A 203(7), 1513 (2006)
“Growth and characterization of single crystalline tin oxide (SnO2) nanowires”, S. Budak, G.X. Miao, M. Ozdemir, K.B. Chetry, A. Gupta, J. Crys. Growth 291(2), 405 (2006)
“A spin triplet supercurrent through the half-metallic ferromagnet CrO2”, R.S. Keizer, S.T.B. Goennenwein, T.M. Klapwijk, G.X. Miao, G. Xiao, A. Gupta, Nature 439(7078), 825 (2006)
“Enhanced magnetic properties of self-assembled FePt nanoparticles with MnO shell”, S.S. Kang, G.X. Miao, S. Shi, Z. Jia, D.E. Nikles, J.W. Harrell, J. Am. Chem. Soc. 128(4), 1042 (2006)
“Inelastic tunneling spectroscopy in magnetic tunnel junctions based on CoFeB / MgO / CoFeB”, G.X. Miao, K.B. Chetry, A. Gupta, W.H. Butler, K. Tsunekawa, D. Djayaprawira, G. Xiao, J. Apply. Phys. 99(8), 08T305 (2006)
“Superparamagnetic nanocomposites based on poly(styrene-b-ethylene / butylene-b-styrene) / cobalt ferrite compositions”, G.S. Rajan, S.L. Stromeyer, K.A. Mauritz, G.X. Miao, P. Mani, M. Shamsuzzoha, D.E. Nikles, A. Gupta, J. Magn. Magn. Mater. 299(1), 211 (2006)
“Giant magnetoresistance structures based on CrO2 with epitaxial RuO2 as the spacer layer”, G.X. Miao, A. Gupta, H. Sims, W.H. Butler, S. Ghosh, G. Xiao, J. Appl. Phys. 97(10), 10C924 (2005)
“Variations in the magnetic anisotropy properties of epitaxial CrO2 films as a function of thickness”, G.X. Miao, A. Gupta, G. Xiao, Phys. Rev. B 71(9), 094418 (2005)
“Epitaxial growth of ruthenium dioxide films by chemical vapor deposition and its comparison with similarly-grown chromium dioxide films”, G.X. Miao, A. Gupta, G. Xiao, A. Anguelouch, Thin Solid Films 478(1-2), 159 (2005)
“The magnetic anisotropy of thin epitaxial CrO2 films studied by ferromagnetic resonance”, B.Z. Rameev, A. Gupta, G.X. Miao, G. Xiao, F. Yildiz, L. R. Tagirov, B. Aktas,Tech. Phys. Lett. 31 (9), 802 (2005)
“Magnetization reversal of CrO2 nanomagnet arrays”, Q. Zhang, Y. Li, A.V. Nurmikko, G.X. Miao, G. Xiao, A. Gupta, J. Appl. Phys. 96(12), 7527 (2004)
“FMR study of strain-induced magnetic anisotropies in CrO2 thin films”, B.Z. Rameev, A. Gupta, G.X. Miao, G. Xiao, F. Yildiz, L.R. Tagirov, B. Aktas,Phys. Status Solidi A 201(15), 3350 (2004)
“Giant Hall resistance in Pt-based ferromagnetic alloys”, G.X. Miao, G. Xiao, Appl. Phys. Lett. 85(1), 73 (2004)
“Properties of epitaxial chromium dioxide films grown by chemical vapor deposition using a liquid precursor”, A. Anguelouch, A. Gupta, G. Xiao, G.X. Miao, D.W. Abraham, S. Ingvarsson, Y. Ji, C.L. Chien, J. Appl. Phys. 91(10), 7140 (2002)