Walter O. Uhoya

**** *** *** *****, ******** Hall 310, Birmingham, AL 35294

Cell: 205-***-**** Email: ab9u71@r.postjobfree.com

EDUCATION:

Doctoral Student in Physics, PhD. Degree Expected in August, 2013

Department of Physics, University of Alabama at Birmingham, Birmingham, AL 35294.

Advisor: Prof. Yogesh. K. Vohra.

Dissertation Title: Phase transitions and anomalous compressibility in 1-2-2 iron-based superconductors under

high pressures.

M.Sc. Physics (Overall GPA of 3.62/4), May, 2010)

College of Arts and Sciences, University of Alabama at Birmingham, Birmingham, AL 35294.

B.Ed. Science (Major: Physics, Minors: Mathematics and Chemistry), November 2005

Graduated with First Class Honors, Moi University, Eldoret, Kenya.

RESEARCH EXPERIENCE:

2011 – Present: User, Spallation Neutron and Pressure Diffractometer (SNAP) Facility at the Spallation Neutron

Source, Oak Ridge National Lab, Oak Ridge, TN 37831.

Investigated crystallographic and magnetic properties of materials under extreme conditions

of pressures and temperatures using time of flight neutron diffraction techniques in a Paris-

Edinburg Cell at SNAP, and Lebail and Rietveld Refinement techniques using GSAS and

FullProf. Also wrote general user beam time proposals for neutron diffraction experiments.

Summer 2011: Graduate Research Student Trainee, Argonne National Lab, 13th National School on

Neutron & X-ray Scattering (NXS), Argonne, IL 60439.

Conducted synchrotron based experiments and analysis on time resolved x-ray diffraction at

beam line 7-ID-C, Small-Angle X-ray Scattering (USAXS) at beam-line 8-ID, hard X-ray

magnetic circular dichroism (XMCD) at beam-line 4-ID-D and transmission electron

microscopy at Advanced Photon Source (APS) in Argonne national Lab.

Summer 2011: Graduate Research Student Trainee, 13th National School on Neutron & X-ray

Scattering (NXS), Oak Ridge National Lab (ORNL), Oakridge, TN 37831.

Conducted neutron based experiments on high pressure time of flight neutron diffraction

using Paris-Edinburg cell at the Spallation Neutron Source (SNS) beam-line BL-3 (SNAP

Pressure Diffractometer); powder diffraction at SNS, beam-line BL-11A (POGWEN);

Extended Q-Range Small Angle Neutron Diffraction (EQ-SANS) at SNS beam-line BL-6 and

Triple Axis Neutron Spectrometer at beam-line HB-3 TAX at High Flux Isotope Reactor

facility in ORNL.

2008 – Present: Graduate Research Assistant, Department of Physics, University of Alabama at Birmingham,

Birmingham, AL 35294.

Conducted structural, magnetic and transport property investigations on Fe-based materials

and rare earth elements under high pressures and cryogenic temperatures.

Experienced a variety of techniques in my measurements including high pressure resistance

and magnetic susceptibility measurements using designer diamond anvil cell, SQUID

magnetization measurements, Raman spectroscopy, energy and angle dispersive x-ray

diffraction.

Wrote beam time proposals; presented results in conferences and journal papers; and trained

selected students during research experience for undergraduates (REU) program at UAB.

Acquired skills in recording, processing and presenting of crystallographic and transport

property measurements data with a number of computer software including Fit2D, FullProf

Suite, EXPGUI/GSAS, SARAh Refine, XRDA, CMPR, Mantid Plot, Igor, Ms Office, PCW,

Labview, Matlab, Maple, Origin, X’pert high score

2008 – Present: User, High Pressure Collaborative Access Team Beam Lines (16-BM-D and 16-ID-B), Advance

Photon Source, Argonne National Lab, Argonne, IL 60439.

Extensively investigated transport and crystallographic properties of novel materials under

extreme conditions of pressures and temperatures using high-pressure diamond anvil cell and

synchrotron based techniques including powder angular dispersive x-ray diffraction, single-

crystal diffraction, and analytical tools including EXPGUI/GSAS and FullProf Rietveld

Refinement Package.

TEACHING EXPERIENCE:

Fall 2006 – 2010: Graduate Teaching Assistant, Department of Physics at the University of Alabama at

Birmingham (UAB), Birmingham, AL 35294.

Taught and evaluated students in at least two of the following physics course, laboratory and

recitation classes. Each class had a mean enrollment of about 30 students and I taught 12 contact

hours per week during fall, summer and spring semesters every year.

PH 201L (Introductory Physics I Labs: Algebra based Mechanics)

PH 221L (General Physics I Labs: Calculus based Mechanics)

PH 222 L (General Physics II Labs: Calculus based Electricity and Magnetism)

PH 202 L (Introductory Physics II Labs: Electricity and Magnetism)

PH 201R (Introductory Physics I Recitation: Mechanics for Freshman and

Sophomore Premed Undergraduates)

PH 222 R (General Physics II Recitation: Electricity and Magnetism)

AST 111L (Preparatory astronomy lab class)

Jan – Aug, 2006: Physics and Mathematics Instructor, Kakamega High School, Kakamega, Kenya.

MENTORING ACTIVITIES/ STUDENT SUPERVISION:

2009 – 2012: Mentor, High Pressure and Material Research Group, Department of Physics, UAB.

Work with my research advisor (Prof. Y. K. Vohra) to mentor REU (Research Experience for

Undergraduates) students and new graduate students of the high pressure physics and materials

research group at UAB.

2007 – 2010: Mentor to Laboratory Teaching Assistants, Department of Physics, UAB.

Work with undergraduate lab director in physics (Dr. Devore) in training and supervising

inexperienced teaching assistants once each week to prepare them in advance on teaching their

assigned physics laboratory classes.

RESEARCH EXERIECE FOR UNDERGRADUATE (REU) STUDENTS SUPERVISED:

Summer 2012: Walter Malone, University of Portland, Portland, Oregon; Research Project: Iron-based

superconductors (transport and magnetic properties investigations under extreme conditions of

high pressures and low temperatures); co-author for a peer review journal article: J.

Phys.: Condens. Matter 24, 495702 (2012).

Summer 2011: Nathaniel Wolanyk, Illinois Wesleyan University, Bloomington, Illinois; Research Project: High

Pressure and Low Temperature Research (synchrotron experiments, transport and magnetic

property measurements); co-authored for an article: European Physical Letters 99, 26002 (2012).

Summer 2010: Mathew Bishop, University of West Georgia, Carrollton, Georgia. Research Project: High

Pressure Synchrotron X- ray diffraction; co-author for peer review journal paper: J. Phys.:

Condens. Matter 22, 425701 (2010).

Summer 2009: Stephen Raiman, The University of Buffalo, Buffalo, New York; Research Project: Iron based

Superconductors.

INTENSIVE TRAINING/PROFFESIONAL SCHOOLS

1. Magnetic Structure Determination Workshop, Oak Ridge National Laboratory, Oak Ridge, TN, Sept 17–20, 2012.

2. 13th National School on Neutron & X-ray Scattering, Oak Ridge National Laboratory (ORNL), Oak Ridge, TN

and Argonne National Laboratory (ANL), Argonne, IL, Summer 2011.

3. Short Course on High Pressure Synchrotron Techniques, Carnegie/DOE Alliance Center (CDAC) and High

Pressure Collaborative Access Team (HPCAT) at Advance Photon Source (APS), Argonne National Laboratory,

Argonne, IL, September 14 –19, 2010.

EDUCATIONAL OUTREACH, PROFFESINAL AND VOLUNTEER ACTIVITIES:

Served as a judge for undergraduate and advanced high school students in a competition for STEM Research

Presentations hosted by Sigma Xi Scientific Honor Society, March, 2013.

Participated in the NSF EPSCoR Science & Technology Open House, Montgomery, AL April 5 – 6, 2013.

Participated in judging science fair projects for Riverchase Middle School in Birmingham, AL, September, 2012.

Volunteer educator in physics and astronomy for the optics bridge summer program for high school students

hosted at the UAB Department of Physics, Summer-2011.

Volunteer to serve as a student member in College of Arts and Sciences Honor Council, UAB, Summer -2011.

Represented the Department of Physics at UAB in volunteer activities including exam proctoring, new graduate

student orientations, standing in as a substitute teaching assistant and REU student mentoring, 2007 to present.

Served as a peer reviewer for Journal of Physics: Condense Matter (one paper), Journal of Physica Scripta (one

paper), Journal of Superconductor, Science and Technology (two papers). I am also listed as volunteer reviewer

for APS and AIP Journals, 2011 to present.

FELLOWSHIPS AND AWARDS:

1. Graduate Research Assistantship, UAB Physics/ DOE National Nuclear Security Administration, 2013 .

2. Recipient, Graduate Research Fellowship, Carnegie/Department of Energy Alliance Center (CDAC), 2010-2013

3. Recipient, Graduate Teaching Assistantship, UAB Department of Physics, Fall 2007-2010.

4. Full Scholarship, The Thirteenth National School on Neutron and X-ray Scattering, supported by DOE Office of

Basic Energy Sciences at Argonne National Laboratory, Argonne, IL and Oak Ridge National Laboratory, Oak

Ridge TN, Summer School 2011.

HONORS AND RECOGNITIONS:

1. 2013 Physics Ph.D. Barker Award Nominee, University of Alabama at Birmingham, Department of Physics.

2. Full Membership Recognition, Sigma Xi, the Scientific Research Honor Society, 2012.

3. Excellence in Scientific Research Award, Department of Physics, University of Alabama at Birmingham, 2011.

4. Outstanding University Teaching Assistant Award, American Association of Physics Teachers (AAPT), 2009.

5. Outstanding Teaching Assistant Award, Department of Physics, University of Alabama at Birmingham, 2008.

6. Full Membership Recognition, Golden Key International Honor Society, 2008.

7. Nominated to serve as student membership on College of Arts and Sciences Honor Council, UAB, Summer, 2011

PROFESSIONAL ORGANIZATION MEMBERSHIPS:

1. Delta Epsilon Iota Academic Honor Society, 2013.

2. Sigma Xi, The Scientific Research Honor Society-2012 to present.

3. American Geophysical Union (AGU) 2011 to present.

4. Society of Physics Students National Organization (SPS), 2011 to present.

5. Neutron Scattering Society of America (NSSA), 2011 to present.

6. Materials Research Society (MRS), 2011 to present.

7. American Physical Society (APS) 2009 to present.

8. American Association of Physics Teachers (AAPT), 2009-2010.

9. Golden Key International Honor Society, 2008 to present.

PEER REVIEWED JOURNAL PUBLICATIONS (2010-2012)

(Over 87 Citations to as per Google Scholar since 2011):

1. S. A. Thomas, W.O. Uhoya, G. M. Tsoi, L.E. Wenger, Y. K. Vohra, G. N. Chesnut, S. T. Weir, C. A. Tulk, A.

M. Santos, “Neutron diffraction and electrical transport studies on the incommensurate magnetic phase transition

in holmium at high pressures,” Journal of Physics: Condensed Matter 24 (21), 216003 (2012).

2. W. Uhoya, G. Tsoi, Y. Vohra, N. Wolanyk, S. M. Rao, M. K. Wu, and S. T. Weir, “Simultaneous measurement

of pressure evolution of crystal structure and superconductivity in FeSe0.92 using designer diamonds,” European

Physical Letters 99, 26002 (2012).

3. Georgiy M. Tsoi, Walter Malone, Walter Uhoya, Jonathan E. Mitchell, Yogesh K. Vohra, Lowell E. Wenger,

Athena S. Sefat, and S. T. Weir, “Pressure Induced Superconductivity in Ba0.5Sr0.5Fe2As2,” Journal of Physics:

Condensed Matter 24, 495702 (2012).

4. W. Uhoya, J. Montgomery, G. Tsoi1, Y. K. Vohra, M. A. McGuire, A. S. Sefat, B.C Sales and S. T. Weir,

“Phase transition and superconductivity of SrFe2As2 under high pressure,” Journal of Physics: Condensed

Matter 22, 122201 (Fast Track Communication), (2011).

5. W. O. Uhoya, G.M. Tsoi, Y.K. Vohra, M.A. McGuire, A.S. Sefat, “Phase transitions in EuFe2As2 superconductor

at low temperatures and high pressures,” Journal of Physics: Condensed Matter 23, 3657031 (2011).

6. W. Uhoya, G. Tsoi, Y. K. Vohra, M. A. McGuire, A. S. Sefat, B. C. Sales, D. Mandrus and S. T.

Weir, “Anomalous compressibility effects and superconductivity of EuFe2As2 under high pressures,” Journal of

Physics: Condensed Matter 22, 292202 (2010), (Fast Track Communication; IOP Select).

7. M. Bishop, W. Uhoya, G. Tsoi, Y. K. Vohra, A. S. Sefat and B. C. Sales, Formation of collapsed tetragonal phase

in EuCo2As2 under high pressure, Journal of Physics: Condensed Matter 22, 425701 (2010).

8. W. Uhoya, A. Stemshorn, G. Tsoi, Y. K. Vohra, A. S. Sefat, B. C. Sales, K. M. Hope, S. T. Weir, “Collapsed

tetragonal phase and superconductivity of BaFe2As2 under high pressure,” Physical Review B 82, 144118 (2010).

9. W. Uhoya, G. M. Tsoi, Y. K. Vohra, M. A. McGuire, A. S. Sefat, B. C. Sales D. Mandrus and S. T.

Weir, “Structural and magnetic phase transitions in NdCoAsO under high pressures,” Journal of Physics:

Condensed Matter 22, 185702 (2010).

10. W. Uhoya, G. M. Tsoi, Y. K. Vohra, A. S. Sefat, S. T. Weir, “Pressure Induced Superconductivity and Structural

Transitions in Ba(Fe0.9Ru0.1)2As2,” under peer review, European Physical Journal B (EPJB).

PEER REVIEWED CONFERENCE PROCEEDINGS:

1. W. Uhoya, J. M. Montgomery, G. K. Samudrala, G. Tsoi, Y. Vohra, S. T. Weir, and A. S. Sefat, “High-pressure

structural phase transitions in chromium-doped BaFe2As2,” J. Phys.: Conf. Series 337, 012016 (2012).

2. W. Uhoya, Georgiy M. Tsoi, Samuel T. Weir, Athena S. Sefat, Mitchell E. Jonathan, Yogesh K. Vohra,

“High Pressure Low Temperature Studies on 1-2-2 Iron-based Superconductors Using Designer Diamonds.” To

be published in 2013 Materials Research Society Spring Meetings Proceedings.

PUBLISHED ABSTRACTS:

1. W.O. Uhoya, G.M. Tsoi, Y.K. Vohra, S.T. Weir, M.A. McGuire, A.S. Sefat, B.C. Sales, D.G. Mandrus, “High

Pressure Kondo-like Behavior in Quaternary Rare Earth Transition Metal Arsenide Oxide,” Bulletin of the

American Physical Society, Volume 55 (2), 2010.

2. Matthew Bishop, Walter Uhoya, Georgiy Tsoi, Yogesh Vohra, Athena Sefat, Brian Sales, “Formation of

collapsed tetragonal phase in EuCo2As2 under high pressure,” Bulletin of the American Physical Society, Volume

56(1), 2011.

3. W. Uhoya, N. Wolanyk, G. Tsoi, Y. Vohra, S.M. Rao, M.K. Wu, S. Weir, “Simultaneous measurement of

pressure evolution of crystal structure and superconductivity in FeSe0.8 using designer diamonds,” Bulletin of the

American Physical Society, Volume 57 (1), 2012.

4. S. Thomas, W. Uhoya, L. Wenger, Y. Vohra, “Magnetic Phase Transition in Rare Earth Metal Holmium at Low

Temperatures and High Pressures,” Bulletin of the American Physical Society, 57(1) 2012.

5. Gary Chestnut, Walter Uhoya, Jeffrey Montgomery, Antonio dos Santos and Jamie Molaison, “High Pressure

Low Temperature Studies of the Iron-Based Superconductor SrFe2As2,” Bulletin of the American Physical

Society, Volume 58 (1) 2013.

CONFERENCE PRENTATIONS:

1. “Anomalous Compressibility Effects and Superconductivity in 1-2-2 Iron-Based Materials under High Pressures,”

NSF EPSCoR Science & Technology Open House, April 5 – 6, 2013, Montgomery, Alabama.

2. “High Pressure Low Temperature Studies on 1-2-2 Iron-based Superconductors Using Designer Diamonds,”

2013 Materials Research Society (MRS) Spring Meeting, April 2, 2013, San Francisco, California.

3. “High Pressure Low Temperature Studies of the Iron–Based Superconductor SrFe2As2,” APS March Meeting,

March 18–22, 2013; Baltimore, Maryland.

4. “Simultaneous measurement of pressure evolution of crystal structure and superconductivity in FeSe 0.8 using

designer diamonds,” APS March Meeting, February 27–March 2, 2012, Boston, Massachusetts.

5. “Magnetic Phase Transition in Rare Earth Metal Holmium at Low Temperatures and High Pressures, APS March

Meeting,” February 27–March 2, 2012; Boston, Massachusetts.

6. “Simultaneous measurement of pressure evolution of crystal structure and superconductivity in FeSe0.92 using

designer diamonds,” 2012 NNSA Stewardship Science Academic Alliances Program Symposium, February 22–

23, 2012, Washington, DC.

7. “Anomalous Compressibility Effects and Superconductivity in 1-2-2 Iron- Base Superconductors under High

Pressures,” 25th Carnegie/Department of Energy Alliance Center (CDAC) Annual Review, October 2011,

Argonne National Lab, Chicago, Illinois.

8. “Structural Phase Transitions in Iron – based Superconductors BaFe2-xCrxAs2 under High Pressures,” 23rd

International Conference on High Pressure Science and Technology, AIRAPT–September 25–30, 2011, Bhabha

Atomic Research Centre, Mumbai 400085, India.

9. “Formation of collapsed tetragonal phase in EuCo2As2 under high pressure, APS March Meeting,” March 21–

March 25, 2011; Dallas, Texas.

10. “Anomalous Compressibility Effects and Superconductivity in 1-2-2 Iron-Based Superconductors under High

Pressures,” NNSA Stewardship Science Academic Alliances Symposium, Feb 14–17, 2011, Washington, DC.

11. “High Pressure Kondo-like Behavior in Quaternary Rare Earth Transition Metal Arsenide Oxide,” American

Physical Society Meeting, March 15–19, 2010, Portland, Oregon.

12. “Structural and Magnetic Phase Transitions in NdCoAsO under High Pressures,” 2010 NNSA Stewardship

Science Academic Alliances Symposium, January 20–22, Washington, DC.

RESEARCH HIGHLIGHTS AND NEWS ARTICLES:

1. “Divining Properties with Designer Diamond Anvil Cells,” Carnegie/Department of Energy (DOE) Alliance

Center (CDAC) Research Highlight: (https://cdac.gl.ciw.edu/component/content/article/445-uhoyaepl2012.html).

2. “Negative Compressibility and Superconductivity in EuFe2As2,” Carnegie/DOE Alliance Center:

(https://cdac.gl.ciw.edu/component/content/article/317-uhoyajpcm2010.html).

3. “Can a collapsed tetragonal phase transition in the pnictides superconductors be accurately predicted?” IOP

Science News Article: (http://iopscience.iop.org/0953-8984/labtalk-article/45678).

4. “Negative compressibility and superconductivity under pressure,” IOP Science News Article:

(http://iopscience.iop.org/0953-8984/labtalk-article/43240).

5. Research Highlight, 2011 Stewardship Science Academic Alliances Annual, DOE/NA-0016, (Page 20), 2011.

Published by Office of Stockpile Steward, National Nuclear Security Administration, U. S Department of Energy,

6. “Low-temperature and high-pressure superconductor phase transitions,” IOP Science Lab Talk News

(http://iopscience.iop.org/0953-8984/labtalk-article/47716).

7. “Divining Properties with Designer Diamonds Anvil Cells,” University of Alabama at Birmingham Student

Spotlight, August 2012 (http://www.uab.edu/physics/component/content/article/155).

GENERAL USER PROPOSAL (GUP) WRITING EXPERIENCE

1. GUP-30815, ‘Simultaneous structural and superconductivity measurements of BaXA1-XFe2As2( A= Sr, Ca, Eu and

0 <x<1) at low temperatures and high pressures,” A GUP for access to APS-Beam line 16-BM-D at Argonne

National Lab; Created on 08/15/2012, Creators: W. Uhoya and Y. K Vohra; 24 shifts of beam time awarded at

16-BM-D APS ; 7 days of experiment completed: beam time current till 2014.

2. IPTS-8093, “Magnetic Transitions in Terbium-Holmium Alloys at High Pressures and Low Temperatures,” A

GUP for access to the Spallation Neutrons and Pressure Diffractometer (SNAP) at Oak-Ridge National Lab;

Created on 23-Aug-2012; Creators; G. Chestnut, W. Uhoya and Y. K. Vohra; Five days for experiments allocated

at SNS BL-3 (SNAP); Experiments Completed.

3. IPTS-7158 “Magnetic Transitions in Terbium at High Pressure and Low Temperatures,” Created on 22-FEB-

2012 ; Creators : G. Chestnut, Y. K. Vohra, and W. Uhoya.

4. IPTS-5921, “High Pressure Neutron Diffraction Study of Iron-Based Superconductor - SrFe2As2,” A GUP for

access to SNAP Facility at Oak Ridge National Lab; Created on 06-SEP-2011; Creators: G. Chestnut, W. Uhoya

and Y. K. Vohra; 4-days of beam time allocated at SNS BL-3 (SNAP); Experiments completed.

5. IPTS-4827, “High Pressure Neutron Diffraction Studies on Iron-Based Superconductors,” Created on 23-Feb-

2011; Creators: Neal G. Chestnut, W. Uhoya and Y. K. Vohra; 4-day s of beam time awarded at BL-3 (SNAP);

Experiments completed from 12-AUG-11 to 16-Aug-11.

6. GUP-28189, “High Pressure Low Temperature Measurements of the Magnetic and Valence State EuFe2As2

Superconductor Using XMCD,” A GUP proposal for access to APS-Beam line 4-ID-D at Argonne National Lab;

Created on 10/28/2011; Creators: W. Uhoya and Y. K. Vohra; Status; 9 shifts of beam time awarded at APS-

Beam line 4-ID-D; current.

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