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Zhao

Guo-meng (Peter) Zhao
Associate Professor
California State University, Los Angeles
Ph.D. 1997, University of Zurich
Office: ASCB 121 C
Telephone: (323) 343-2139    
Specialization: Experimental condensed matter physics
                                                                                   

Education

 

7/97                Ph.D. in Physics, Physics Department, University of Zurich with K. A. Muller (Nobel Laureate, 1987)

12/90               M. A. in Physics, Physics Department, University of Southern California

9/85-7/88         Ph. D. Candidate, Physics Institute, Chinese Academy of Sciences

7/85                 B.S. in Physics, Zhejiang University, Hangzhou, China

 

Professional Experience

 

9/08                Associate Professor, Department of Physics and Astronomy, California State University, Los Angeles                   

9/02-8/08        Assistant Professor, Department of Physics and Astronomy, California State University, Los Angeles

5/01-8/02        Research Associate Professor, Physics Department/TcSUH, University of Houston

7/97-5/01        Faculty Research Associate, Physics Department, University of Zurich

12/97-6/98      Research Associate, Center for Superconductivity Research, Physics Department,

                        University of Maryland

 

Scholarly Highlights

  • 99 publications (including 2 Nature, 7 Physical Review Letters, 37 Physical Review B, 1 Applied Physics Letters, 5 Journal of Applied Physics, and 9 Book Chapters)

  • Over 2500 citations including over 600 citations to the 96 Nature paper

  • Invited speaker in 14 international conferences including an invited speaker in the APS March Meeting

  • Over 30 colloquia/seminars in the academic and research institutions including the Stanford University, the Brown University, USC, UCLA, Tsinghua University, and UTSC

  • First observation of a giant oxygen-isotope shift of the Curie-temperature in doped manganites (discovery of a novel isotope effect, published in Nature in 1996)

  • First observation of a large oxygen-isotope effect on the effective supercarrier mass in superconducting cuprates (discovery of a novel isotope effect, published in Nature in 1997), demonstrating polaronic nature of supercarriers, which is crucial to the understanding of the microscopic origin of high-temperature superconductivity

  • First observations of many unconventional isotope effects in perovskite oxides, directly demonstrating very strong electron-phonon interactions and the existence of polaronic/bipolaronic charge carriers in these materials

  • Identification of the intrinsic gap (pairing) symmetry in the bulk of high-temperature superconductors, which is extended s-wave (s+g wave) with eight line nodes in hole-doped cuprates, and nodeless s-wave in electron-doped cuprates. This important conclusion is in contrast to the extrinsic d-wave symmetry inferred from some surface and phase-sensitive experiments

  • Identification of bosonic modes mediating electron pairing for high-temperature superconductors, showing evidence for predominantly phonon-mediated pairing mechanism and ruling out magnetic pairing mechanism

  • Proof for bipolaronic superconductivity in underdoped cuprates

  • Providing strong evidence for phase-incoherent ultrahigh temperature superconductivity in carbon nanotubes

  • First observation of giant magnetic moment enhancement of magnetic nanoparticles embedded in multi-walled carbon nanotubes

  • First observation of anomalous thermal hysteresis of the high-field magnetic moment of magnetic nanoparticles embedded in multi-walled carbon nanotubes: Consistent with the high-field paramagnetic Meissner effect due to ultrahigh temperature superconductivity in carbon nanotubes

  • First observation of finite-size scaling relations in several magnetic nanoparticle systems: Quantitative agreement with theory

  • First identification of the intrinsic correlation length exponent in nickel: Resolving a long-standing controversy in the field

 

Professional Activities

  • Session Chair in 1999 APS March Meeting

  • Session Chair in the 32nd Condensed Matter Theory Workshop, 2008

  • Referee for Physical Review B, Physical Review Letters, Applied Physics Letters, Journal of Applied Physics, Physics Letters, and over 10 other physics journals

  • Editorial Advisory Board Member to Open Condensed Matter Physics Journal, Open Condensed Matter Physics Reviews, and Open Condensed Matter Physics Letters

 

Honors and Awards

  • Recipient of the most outstanding Ph.D. dissertation award, University of Zurich, Switzerland, 1997
  • Recipient of the most outstanding undergraduate student award, Zhejiang University, China, 1983
  • Cottrell college science award from Research Corporation (2004 and 2005)

 

Research Interests

 

My research interests include studying novel materials exhibiting extraordinary superconducting, magnetoresistive, ferroelectric, optical, and magnetic properties. These novel materials include high-temperature superconducting cuprates, colossal magnetoresistive manganites, ferroelectric and photorefractive barium titanates, and quasi-one-dimensional carbon nanotubes. I am particularly interested in unconventional oxygen-isotope effects on electrical, magnetic, and thermal properties of the provskite oxides to clarify the roles of electron-phonon interactions in the microscopic origins of high-temperature superconductivity in cuprates, the colossal magneteoresistance in manganites, and the unusual photorefractive effect in barium titanates. I am also interested in theoretical studies of the pairing interactions and gap symmetry in cuprates to provide essential constraints on the microscopic theory of high-temperature superconductivity. My current experimental research focuses on magnetic and superconducting nanostructures, magnetic nanoparticles embedded in multi-walled carbon nanotubes.