SCIENCE AND TECHNOLOGY OF SELFASSEMBLED MAGNETIC AND SUPERCONDUCTING NANO ARRAYS Dhananjay Kumar, No

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SCIENCE AND TECHNOLOGY OF SELF-ASSEMBLED MAGNETIC
AND SUPERCONDUCTING NANO ARRAYSDhananjay Kumar,
North Carolina A T State University, DMR 0403480

• Nanodots of CeO2 on LaAlO3(LAO) substrates,
  generated in situ by means of a pulsed laser
  deposition method prior to the deposition of
  YBCO films, have been used to modify the
  superconducting properties of resulting YBCO
  films.
• Surface of islands facetted with two orientation
  relationships
• OR-I (001) 110CeO2//(001)100LAO
• OR-II (110) 110CeO2//(001)100LAO
• Results have shown that CeO2 can affect the
  superconducting properties of YBCO films
  favorably or adversely depending on the density
  of CeO2 nanodots.

• The role of spacer layer thickness was
  investigated by making layered thin film
  composites with various spacer layer thicknesses
  (10-25 nm,) with fixed iron particle size of 13
  nm (Fig. a and b).
• Intralayer magnetic interactions being the same
  in each sample, the variation in coercivity
  (Fig. c) is attributed to thickness dependent
  interlayer magnetic interactions of three types
  exchange, strong dipolar and weak dipolar.
• A thin film composite multilayer structure offers
  a continuously tunable strength of interparticle
  dipole- dipole interaction and is thus well
  suited for studies of the influence of
  interaction on the magnetic properties of small
  magnetic particle systems.

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SCIENCE AND TECHNOLOGY OF SELF-ASSEMBLED MAGNETIC
AND SUPERCONDUCTING NANO ARRAYSDhananjay Kumar,
North Carolina A T State University, DMR 0403480
New Course Development The course, New Methods
in Thin Film Synthesis developed under this
program, has been inducted as a permanent course
in the Mech. Eng. Dept. at NCAT. Infrastructure
development A physical property measurement
system, purchased in this project, is run 24/7
and is used by more than 5 faculties and 15
graduate and undergraduate students enhancing
their research and educational standard
significantly. Students Graduated A. Paige, T.
Haywood, MS ( NCAT) Ramachandran, Ph.D.
(NCSU) Current Students N. Herndon, MS (NCAT),
G. Trichy, Ph.D. (NCSU) R. Das, Ph.D. (UF) Semi
Ghabrazadic, Undergraduate (NCAT). Post doc
supported J. Abiade, Sang Ho Oh (NCAT), N.
Sudhakar (NCSU) Salient Publications (total
exceeds 10) Thin Solid Films 515, 6452 (2007),
Appl. Phys. Lett. 90, 132511 (2007), 89, 132502
(2006), J. Nanoparticle Res. 8, 595(2006), J.
Electrochem. Society (2006), 153, G1001-G1004,
Book Current and Future Trends of Functional
Oxide Films Publisher Materials Research
Society (2006) Technical presentation (more
than 10) Kumar (2 MRS), Hebard (2 APS), Narayan
(4 MRS, TMS), Abiade (2), Oh (2) International
dissemination of results NIRT-PI was the lead
organizer of a symposium during MRS 2006 Spring
Meeting in San Francisco that had 15 invited
oral presentations, 50 contributed oral
presentations, and 30 poster presentations from
within and outside USA. Outreach Reached to more
than 100 K-12 students and teachers through lab
visits, school trips, short experiments