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Welcome to Xiaohang's Homepage

 

 

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Xiaohang Zhang, Ph.D.

 

0368 John S. Toll Building

Center for Nanophysics & Advanced Materials, University of Maryland

College Park, MD 20742

 

Office Phone #: (301)-405-8145

Email: xhzhang@umd.edu

 

Curriculum Vitae [PDF]

 

 

Research Interest

My research interest is the study of emergent physical phenomena of novel materials and their hybrid structures. My current research efforts are mainly focused on four specific topics: 1) topological insulators and their devices; 2) magnetic materials and spintronics; 3) correlated electron physics; 4) superconductivity of iron pnictides. It is highly expected that the exotic physical properties of these materials and their hybrid structures will be exploited to develop the next generation electronics. The goal of my research is to explore the physics of the emergent behaviors and pursue device applications. To this end, various fabrication techniques such as thin film deposition, single crystal growth, and lithography, etc. are used for material synthesis and device fabrication while electronic transport and thermal electric effect measurements at low temperature and/or in high magnetic field are performed as the primary investigation tools. 

Education

  • 2002-2008         Ph.D.                   Condensed Matter Physics         Florida State University
  • 1998-2001         Master                 Nuclear Engineering                   Tsinghua University, China
  • 1993-1998         Bachelor              Engineering Physics                    Tsinghua University, China

Professional Experience

Experimental Skills

  • Fabrication: thermal and electron-beam evaporation, magnetron sputtering, pulsed laser deposition, photolithography, reactive ion etching, single crystal growth by flux method.
  • Cryogenic and Transport Measurement Experience: electronic and thermal transport, tunneling spectroscopies, low-noise electronics, He-4, He-3, and dilution refrigeration cryostats, high-field (up to 45T) measurement experience, LabView programming.  
  • Other Measurement Experience: XRD, XRR, AFM, PFM, SEM, XPS, SQUID, VSM, and neutron scattering measurement experience.

Publications

  1. Xiaohang Zhang, S. A. McGill, and P. Xiong, Xiaolei Wang, Jianhua Zhao, Probing the Thiol-Gold Planar Interface by Spin Polarized Tunneling, Applied Physics Letters 104, 152403 (2014). [Link] [PDF]
  2. Xiaohang Zhang, N. P. Butch, P. Syers, S. Ziemak, R. L. Greene, and J. Paglione, Hybridization, Correlation, and In-Gap States in the Kondo Insulator SmB6. Physical Review X 3, 011011 (2013) [Link] [PDF] [Highlighted by APS Physics and Reported by Nature News]
  3. Liuqi Yu, Lingfei Wang, Xiaohang Zhang, W. B. Wu, S. von Moln¨˘r, Z. Fisk, and P. Xiong, Signatures of Electronic Phase Separation in the Hall Effect of Anisotropically Strained La0.67Ca0.33MnO3 Films. New Journal of Physics 15, 113057 (2013). [Link] [PDF]
  4. Xiaohang Zhang, B.-S. Lee, S.-H Khim, K.-H Kim, R. L. Greene, and I. Takeuchi, Measurement of the order parameter of superconducting LiFeAs in Pb/LiFeAs and Au/LiFeAs junctions by point-contact spectroscopy, Physical Review B 85, 094521 (2012). [Link] [PDF]
  5. K. Jin, P. Bach, X. H. Zhang, U. Grupel, E. Zohar, Y. Dagan, S. Smadici, P. Abbamonte, and R. L. Greene, Anomalous Enhancement of the Superconducting Transition Temperature in Electron-doped La2-xCexCuO4 and Pr2-xCexCuO4 Cuprate Heterostructures. Physical Review B 83, 060511 (Rapid Communication) (2011). [Link] [PDF]
  6. Xiaohang Zhang, Y. S. Oh, Y. Liu, L. Q. Yan, S. R. Saha, N. P. Butch, K. Kirshenbaum, K. H. Kim, J. Paglione, R. L. Greene, and I. Takeuchi, Evidence of a universal and isotropic 2Ś¤/kBTC ratio in 122-type iron pnictide superconductors over a wide doping range, Physical Review B 82, 020515 (Rapid Communication & EditorsĄŻ Suggestion) (2010). [Link] [PDF]
  7. N. P. Butch, S. R. Saha, Xiaohang Zhang, K. Kirshenbaum, R. L. Greene, and J. Paglione, Effective Carrier Type and Field-Dependence of the Reduced-TC Superconducting State in SrFe2-xNixAs2, Physical Review B 81, 024518 (2010). [Link] [PDF]
  8. B. Saparov, H. He, X. H. Zhang, R. Greene, and S. Bobev, Synthesis, Crystallographic and Theoretical Studies of the New Zintl Phases Ba2Ca2Pn3 (Pn = As, Sb), and the Solid Solutions (Ba1-xSrx)2Cd2Sb3 and Ba2Cd2(Sb1-xAsx)3, Dalton Transactions 39, 1063 (2010). [Link] [PDF]
  9. Xiaohang Zhang, L. Q. Yu, S. von Moln¨˘r, Z. Fisk, and P. Xiong, Nonlinear Hall Effect as a Signature of Electronic Phase Separation in the Ferromagnetic Semimetal EuB6, Physical Review Letters 103, 106602 (2009). [Link] [PDF]
  10. Xiaohang Zhang, S. R. Saha, N. P. Butch, K. Kirshenbaum, Y. Liu, L. Q. Yan, Y. S. Oh, K. H. Kim, J. Paglione, R. L. Greene, and I. Takeuchi, Josephson Effect Between Electron-Doped and Hole-Doped Iron Pnictide Single Crystals, Applied Physics Letters 95, 062510 (2009). [Link] [PDF]
  11. Xiaohang Zhang, Y. S. Oh, Y. Liu, L. Q. Yan, K. H. Kim, R. L. Greene, and I. Takeuchi, Observation of the Josephson Effect in Pb/Ba1-xKxFe2As2 Single Crystal Junctions, Physical Review Letters 102, 147002 (2009). [Link] [PDF]
  12. K. Jin, X. H. Zhang, P. Bach, and R. L. Greene, Evidence for Antiferromagnetic Order in La2-xCexCuO4 from Angular Magnetoresistance Measurements, Physical Review B 80, 012501 (2009). [Link] [PDF]
  13. Xiaohang Zhang, S. von Moln¨˘r, Z. Fisk, and P. Xiong, Spin-Dependent Electronic States of the Ferromagnetic Semimetal EuB6, Physical Review Letters 100, 167001 (2008). [Link] [PDF]
  14. Xiaohang Zhang, S. A. McGill, and P. Xiong, Origin of the Humidity Sensitivity of  Al/AlOx/MHA/Au Molecular Tunnel Junctions, Journal of the American Chemical Society 129, 14470 (2007). [Link] [PDF]
  15. Xiaohang Zhang, Studies of Novel Magnetic Materials and Interfaces via Electronic Transport and Superconducting Spectroscopy, Ph. D. Thesis, Florida State University (2008). [Link] [PDF]

Conference Invited Presentations

  1. Josephson Effect studies of pairing symmetry in Fe-based superconductors, American Physical Society March Meeting, Portland, OR, March 2010.
  2. Nonlinear Hall effect as a signature of electronic phase separation, 55th Magnetism and Magnetic Materials Conference, Atlanta, GA, November, 2010.

Department Colloquiums

  1. George Mason University, April 14th, 2014.
  2. NIST Center for Neutron Research, January 27th, 2014.
  3. Department of Physics and Astronomy, University of Missouri ¨C Columbia, April 4th, 2013.
  4. Department of Physics and Astronomy, University of Nebraska ¨C Lincoln, March 25th, 2013.
  5. Department of Physics, New York University, March 3rd, 2008.

Conference Presentations 

  1. Magnetoresistance, Hall effect, and point contact tunneling spectroscopy of superconducting LiTi2O4 thin films (Talk), American Physical Society March Meeting, Denver, CO, March 2014.
  2. Evolution of the coherent state and the electronic structure in the Kondo insulator SmB6 (Talk), American Physical Society March Meeting, Baltimore, MD, March 2013.
  3. Giant magnetoresistance spin valves exchange-biased by ferroelectric BiFeO3 thin films (Talk), American Physical Society March Meeting, Baltimore, MD, March 2013.
  4. Probing the superconducting order parameter of LiFeAs via point contact spectroscopy (Poster), 10th Materials and Mechanisms of Superconductivity Conference, Washington, D.C., July-August 2012.  
  5. Point Contact Andreev-reflection studies on iron pnictide superconductors (Talk), American Physical Society March Meeting, Dallas, TX, March 2011.
  6. Josephson effect and Andreev-reflection studies on the 122 iron pnictide single crystals (Poster), Applied Superconductivity Conference, Washington, D.C., August 2010.
  7. Observation of the Josephson Effect in Pb/(Ba,K)Fe2As2 Single Crystal Junctions (Talk), American Physical Society March Meeting, Pittsburgh, PA, March 2009.
  8. Spin-dependent band structure of the ferromagnetic semimetal EuB6 (Talk), American Physical Society March Meeting, New Orleans, LA, March 2008.
  9. Unusual Hall effect due to carrier delocalization (Talk), American Physical Society March Meeting, New Orleans, LA, March 2008.
  10. Spin-dependent electronic states of the ferromagnetic semimetal EuB6 (Talk), 52nd Magnetism and Magnetic Materials Conference, Tampa, FL, November 2007.
  11. Probing the thiol-gold interface by spin polarized tunneling (Talk), 52nd Magnetism and Magnetic Materials Conference, Tampa, FL, November 2007.
  12. Spin Polarization of the ferromagnetic semimetal EuB6 (Talk), American Physical Society March Meeting, Denver, CO, March 2007.
  13. Tunneling study of organic-inorganic interfaces in molecular junctions (Poster), Materials Research Society Fall Meeting, Boston, MA, November 2006.
  14. Humidity dependence of molecular tunnel junctions with an AlOx/COOH- interface (Talk), American Physical Society March Meeting, Baltimore, MD, March 2006.

Contributed over 25 other conference presentations.

Professional Services

  • Referee for 15+ journals including Science, Physical Review Letters, Physics Review B, Applied Physics Letters, Journal of Applied Physics, New Journal of Physics, Superconductor Science & Technology, etc.

Memberships 

  •  American Physical Society (2005 - present)

Awards 

  • NIST-ARRA Fellowship (Oct. 2011 ¨C Sept. 2013)

Links

University of Maryland                      Department of Physics, UMD                   Center for Nanophysics and Advanced Materials

Florida State University                     Department of Physics, FSU                     American Physical Society

National Standards and Technology

This site was last updated 4/16/2014