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Seminar by Sai Gautam Gopalakrishnan (3.30pm, 18 Jan 2016)

Title : “First-principles Study of Vanadium(V) Oxide Polymorphs as Cathode Materials for Mg (and multi-valent) Batteries”

Speaker : Sai Gautam Gopalakrishnan

Affiliation: Department of Materials Science and Engineering, Massachusetts Institute of Technology, USA.

Date : Monday, January 18, 2016

Time : 3:30 PM;

Venue : Lecture Theater, Department of Materials Engineering,

Seminar Series by Prof. Kannan Krishnan

[Update: Please note the change in the date for the first seminar; it will be held on Tuesday, 12.1.2016]

* * *

Prof. Kannan M. Krishnan (Department of Materials Science & Engineering, and Physics, University of Washington, Seattle, USA) is currently a Brahm Prakash Visiting Chair in our Department (see below for his biosketch). He will deliver a series of three seminars during January 2016:

  1. From materials to medicine: a sp↑n through recent developments in imaging, therapy and diagnostics (Tuesday, 12.1.2016)
  2. Magnetism on the mesoscale: Nanotechnology, Lithography, Information Storage and Logic (Wednesday, 13.1.2016)
  3. Magnetism, microstructure and materials characterization (date to be announced)

All the seminars will be at 3:30 p.m. in the Lecture Theatre of the Department of Materials Engineering. Please see the notices for the individual seminars for their abstracts: Seminar 1, Seminar 2, and Seminar 3).

* * *

Prof. Kannan M. Krishnan

Kannan M. Krishnan obtained his B. Tech (Mech. Eng.) from IIT Kanpur and Ph.D. (Materials Science; Minor in Physics & Mathematics) from UC, Berkeley. After graduation in 1984, he held various scientific and teaching positions at Lawrence Berkeley National Laboratory and UC, Berkeley, before joining the University of Washington, in 2001, as the Campbell Chair Professor of Materials Sciences & Engineering and Adjunct Professor of Physics. He has held visiting appointments in all six continents including the Hitachi Central Research Laboratory (Japan), Tohoku University, Danish Technical University, University of Sao Paolo, University of Western Australia, University of Alexandria (Egypt), and the Indian Institute of Science.

Prof. Krishnan’s current research focus is broadly on two major, inter-related themes: (i) Bioengineering at the intersection of Magnetism, Materials and Medicine focusing on diagnostics, imaging and therapy, with appropriate translational research and commercialization activities. (ii) Materials Engineering & Condensed Matter Physics with emphasis on nanoscale magnetic and transport (both charge and spin) phenomena in reduced dimensions, including their inter-coupling and structure-property correlations at relevant length scales, to develop paradigms for materials and devices in the context of information (storage, processing and logic) and energy technologies.

Prof. Krishnan is widely recognized for research, teaching, mentoring and entrepreneurship. He has received the TMS/FMD Distinguished Scientist/Engineer Award (2015), IEEE Donald G. Fink Prize (2012), Fulbright Specialist Award (2010), IEEE Magnetics Society Distinguished Lecturer Award (2009), Guggenheim Fellowship (2004), the Rockefeller Bellagio Fellowship (2008), the Burton Medal (Microscopy Society of America, 1992), JSPS Senior Scientist Fellowship (2002), the College of Engineering Outstanding Educator Award (UW, 2004), an appointment as the Professor-at-large (University of Western Australia, 2006-8) and a nomination as the UW candidate for the AAAS Mentor award (2009). Based on his teaching and scholarship, his comprehensive 820-page single author book, entitled “Fundamentals and Applications of Magnetic Materials”, will be published by Oxford University Press in 2016. He is an elected Member of the Washington State Academy of Science, and Fellow of the American Association for the Advancement of Science, the American Physical Society, the Institute of Physics (London) and the Institute of Electrical and Electronics Engineers (IEEE). He has served on the editorial boards of the Journal of Materials Science, Journal of Magnetism and Magnetic Materials, Acta Materialia, Journal of Physics D: Applied Physics, IEEE Magnetics Letters and Medical Physics. His service activities are extensive and include the UW College of Engineering Promotion and Tenure Council (2001-5), the UW Common Book selection committee (2010), the IEEE Magnetics Society Administrative Committee (2011-3) and the Fetzer Institute Advisory Council on the Engineering Professions (2011-3).

In 2010, along with two former graduate students, he has founded a start-up company, LodeSpin Labs, involved in the development of tailored magnetic carriers for a range of biomedical applications.

Seminar Series by Prof. Kannan Krishnan – 3

Department of Materials Engineering
Indian Institute of Science

is pleased to invite you to the seminar on

Magnetism, microstructure and materials characterization
by
Prof. Kannan M. Krishnan
Brahm Prakash Visiting Chair
Department of Materials Engineering
Indian Institute of Science, Bangalore
and
Department of Materials Sciences & Engineering, and Physics
University of Washington
Seattle, USA

at 3:30 p.m.
on (Date to be announced)
in the Lecture Theatre, Department of Materials Engineering.

Abstract

Magnetic materials, subtle in their manifestation, are electronically driven with their origin in the Pauli exclusion principle and the existence of electron spin. They are known for a variety of both classical and quantum-mechanical effects, arising from both short- and long-range forces, and are widely associated with “microstructure” or the morphological arrangements of magnetic moments (domains), as well as phases, grains, or individual atoms themselves. These are, in part, the reason for the richness in properties and technological applications encountered in magnetic systems. These are also, in part, why the magnetic behavior of materials is poorly understood [1].

In this talk, with a materials science structure-property-processing perspective, and drawing on our work on a wide range of materials [2] (nanoparticles [3], doped semiconducting oxides [4] and epitaxially grown metallic heterostructures [5]), I will describe their behavior at relevant length scales. Advanced characterization techniques using transmission electron microscopy (electron energy-loss spectroscopy, holography [6], energy-filtered imaging [7], atomic column-by-column z-contrast imaging) and synchrotron radiation [8] (x-ray absorption spectroscopy, x-ray magnetic circular dichroism and x-ray magnetic reflectivity [9]) are integral to these studies.

Specific topics to be addressed include:

  • Self-assembly [10], inter-particle magnetic interactions/order [11] and “memory” in magnetic nanoparticle systems
  • Defect-mediated ferromagnetism [12] in transition-metal-doped dilute magnetic semiconductors
  • Exchange-bias [13], asymmetric magnetic reversal [14] and the role of buried interfaces [15] in epitaxial heterostructures [16].

1. Kannan M. Krishnan, Fundamentals and applications of magnetic materials, Oxford University Press, 820pp, ISBN 9780199570447 (Available, Summer 2016)

2. Kannan M. Krishnan et al, Jour. Mat. Sci. 41, 793–815 (2006)

3. V. F. Puntes, Kannan M. Krishnan and P.A. Alivisatos, Science, 291, 2115-2117 (2001).

4. K. G. Roberts, M. Varela, S. Rakshev, S. Pantelides, S. J. Pennycook and Kannan M. Krishnan, Phys, Rev. B 78, 014409 (2008)

5. Wei Zhang and Kannan M. Krishnan, “Epitaxial exchange-bias systems: from fundamentals to spin-orbitronics”, Materials Science & Engineering – R: Reports (in press)

6. Y. Takeno, … Kannan M. Krishnan, Appl. Phys. Lett. 105, 183102 (2014)

7. W. Grogger, B. Schaffer, Kannan M. Krishnan and F. Hofer, Ultramicroscopy 96, 481-489 (2003).

8. G. Srajer et al, Jour. Mag. Mag. Mat. 307, 1-31 (2006)

9. Sebastian Brück et al, Phys. Rev. B 81 134414 (2010)

10. Y. Bao, M. Beerman and Kannan M. Krishnan, Jour. of Mag. Mag. Mat., 272-276, Supp1, E1367-E1368 (2004)

11. Y. Gao, Y. Bao, A. B. Pakhomov, Daisuke Shindo and Kannan M. Krishnan, Phys. Rev. Lett., 96, 137205 (2006)

12. K.A. Griffin, A.B. Pakhomov, C.M. Wang, S.M. Heald, Kannan M. Krishnan, Phys. Rev. Lett., 94, 157204 (2005)

13. W. Zhang and Kannan M. Krishnan, Jour. Micromech. & Microeng. 24, 093001 (2014)

14. P. Blomqvist, Kannan. M. Krishnan and H. Ohldag, Phys. Rev. Lett., 94, 107203 (2005)

15. S. Bruck, E. Goering, G. Schutz, X. Ji and Kannan M. Krishnan, Phys. Rev. Lett. 101, 126402 (2008)

16. This work was supported by US-Grants DOE DE-AC03-76SF00098, DoE/BES ER-45987, NSF/DMR #0203069, NSF/DMR #0322729, NSF/ECS #0224138, NSF/DMR #0315460

Seminar Series by Prof. Kannan Krishnan – 2

Department of Materials Engineering
Indian Institute of Science

is pleased to invite you to the seminar on

Magnetism on the mesoscale: Nanotechnology, Lithography, Information Storage and Logic
by
Prof. Kannan M. Krishnan
Brahm Prakash Visiting Chair
Department of Materials Engineering
Indian Institute of Science, Bangalore
and
Department of Materials Sciences & Engineering, and Physics
University of Washington
Seattle, USA

at 3:30 p.m.
on 13.1.2016 (Wednesday)
in the Lecture Theatre, Department of Materials Engineering.

Abstract

There has been a renaissance in magnetism and magnetic materials research on the nanometer length scale, largely driven by size-dependent scaling laws, exchange, proximity and interface effects, advances in fabrication [1,2], and their demonstrated impact in information technologies.

I will begin this lecture with a brief discussion of criteria that define Nanoscience and Nanotechnology and illustrate them with characteristic length scales and size effects that make magnetism ideal, not only for fundamental investigations, but also technological developments on this length scale.

In the second part of this lecture, I will present recent developments in lithographic fabrication of nanoscale elements, emphasizing the facile, low-cost method of nanoimprint lithography. I will then illustrate some fundamental magnetic studies of competing anisotropies in epitaxial grown nanowire arrays [3], manipulating domain wall reversal by shape anisotropy [4] and the properties of three-dimensional “sombrero” shaped s structures [5,6].

Next, I will address the current status of magnetic recording media and discuss the development of next-generation bit-patterned media [7], proposed to sustain the current growth rate of recording densities. I will conclude with a discussion of a novel concept of building Boolean logic gates [8], called magnetic quantum cellular automata, based purely on dipolar coupling of magnetic arrays [9].

1. Wei Zhang and Kannan M. Krishnan, “Epitaxial patterning of thin films: conventional lithographies and beyond”, Jour. Micromech. & Microeng. 24, 093001 (2014)

2. Y. Bao, T. Wen, A.C. Samia, A.P. Khandhar, and Kannan M. Krishnan, “Magnetic Nanoparticles: Materials Engineering and Emerging Applications in Lithography and Biomedicine”, Jour Mater. Sci. , 51, 513-553 (2016)

3. Wei Zhang, Mark E. Bowden and Kannan M. Krishnan, “Nanoimprint-lithography patterned epitaxial Fe nanowire arrays with misaligned magnetocrystalline and shape anisotropies”, Jour. Appl. Phys. 113 17B502 (2013)

4. W. Zhang, D. N Weiss and Kannan M Krishnan, “ Thermal nanoimprint process for high-temperature fabrication of epitaxial exchange-biased metallic nanostructures”, Jour. Micrmech. Microeng. 21, 045204 (2011)

5. Byung Seok Kwon, Wei Zhang and Kannan M. Krishnan, “Sombrero-shaped Fe3O4 nanoelements with tunable out-of-plane and in-plane magnetization components fabricated by nano-imprint lithography”, Jour. Appl. Phys. 115, 17B506 (2014

6. Byung-Seok Kwon, Wei Zhang and Kannan M. Krishnan, “Direct release of Bio-compatible Sombrero-shaped Magnetite Nanoparticles via Nanoimprint Lithography”, Advanced Materials – Interfaces, 2, 1400511 (2015)

7. Zheng Li, Wei Zhang+ and Kannan M. Krishnan, “Large-area patterning of sub-100 nm L10 FePt dots array”, AIP Advances. 5, 087165 (2015)

8. Zheng Li and Kannan M. Krishnan, “Misalignment-free signal propagation in nanomagnet arrays and logic gates with 45°-clocking field”, Jour. Appl. Phys. 115, 17E502 (2014)

9. This work was supported by US-DOE/BES Grant ER45987 and US-NSF Grant DMR-1063489

Seminar Series by Prof. Kannan Krishnan – 1

Department of Materials Engineering
Indian Institute of Science

is pleased to invite you to the seminar on

From materials to medicine: a sp↑n through recent developments in imaging, therapy and diagnostics
by
Prof. Kannan M. Krishnan
Brahm Prakash Visiting Chair
Department of Materials Engineering
Indian Institute of Science, Bangalore
and
Department of Materials Sciences & Engineering, and Physics
University of Washington
Seattle, USA

at 3:30 p.m.
on 12.1.2016 (Tuesday)
in the Lecture Theatre, Department of Materials Engineering.

Abstract

The Néel relaxation of magnetic nanoparticles (MNP), subject to alternating magnetic fields in solution, depends exponentially on the size of their magnetic core, whilst the complementary Brownian relaxation mechanism depends critically on their hydrodynamic volume [1,2]. Recent developments in the synthesis [3] and applications [4] of highly monodisperse and phase-pure magnetite nanoparticles, with negligible toxicity [5] and favorable biodistribution [6], allows for reproducible control of the former, even in “harsh” biological environments, enabling novel imaging [7,8,9], spectroscopic [10] and therapeutic1112 modalities, under ac excitations. With appropriate functionalization of the monodisperse cores, and utilizing the magnetic relaxation, it also allows for the development of sensitive, relaxation based assays13 for the detection of biomolecules associated with various diseases.

In this multidisciplinary talk, beginning with the physics of magnetic relaxation under ac excitation, I will describe the chemical synthesis, phase optimization, surface functionalization, and development of optimized nanoparticle tracers with magnetic properties tailored for the unique physics of Magnetic Particle Imaging –– an emerging tracer-based whole body imaging technique with no ionizing radiation, and present recent results in phantom and in vivo imaging of animal models for cardiovascular disease and molecular imaging of cancer. I will also present details of newly designed assays, using magnetic particle spectroscopy, for the detection of proteases that are closely linked to malignant phenotypes of different solid tumors and conclude with an outlook of opportunities that abound for continued research in this exciting field [14].

1. Kannan M. Krishnan, IEEE Trans. Mag. 46, 2523-2558 (2010)

2. C. Kuhlmann, A. P. Khandhar, R. M. Ferguson, S. Kemp, T. Wawrzik, M. Schilling, Kannan M. Krishnan and F. Ludwig, IEEE Trans. Mag. 51, 6500504 (2015)

3. R. Hufschmid, H. Arami, R. M. Ferguson, M. Gonzales, E. Teeman, L. Brush, N. Browning and Kannan M. Krishnan, Nanoscale, 7, 11142 (2015)

4. Y. Bao, T. Wen, A.C. Samia, A.P. Khandhar, and Kannan M. Krishnan, Jour Mater. Sci., 51, 513-553 (2016)

5. H. Arami, A. Khandhar, D. Liggitt and Kannan M. Krishnan, Chem. Soc. Rev. 44, 8576 (2015)

6. H. Arami, A. P. Khandhar, A. Tomitaka and Kannan M. Krishnan, Biomaterials 52, 251 (2015)

7. B. Gleich & J. Weizenecker, Nature 435, 1214 (2005).

8. R.M. Ferguson, A.P. Khandhar, H. Arami, E.U. Saritas, L.R. Croft, P.W. Goodwill, A. Halkola, J. Rahmer, J. Borgert, S.M. Conolly and Kannan M. Krishnan, IEEE Trans. Med. Imag. 34, 1077 (2015)

9. A. Tomitaka, S. Gandhi, H. Arami and Kannan M. Krishnan, Nanoscale 7, 16890-16898 (2015).

10. S. A. Shah, D.B. Reeves, R.M. Ferguson, J.B. Weaver, and Kannan M. Krishnan, Phys. Rev. B92, 094438 (2015)

11. A. Khandhar, R. Matthew Ferguson, Julian A. Simon and Kannan M. Krishnan, Jour. Biomedical Materials Research, Part A, 100A, 728-737 (2012)

12. S. Kalale, R. Narain and Kannan M. Krishnan, Jour. Mag. Mag. Mat. 321, 1377-1380 (2009)

13. S. Gandhi, H. Arami, Kannan M. Krishnan, Proc. Nat. Acad. Sci., (submitted)

14. This work was supported by US-NIH Grants 1RO1EB013689-01/NIBIB, 1R41EB013520-01, and 2R42EB013520-02A1.

29th Annual Students’ Symposium, 21-22 Jan 2016

Preamble

The First edition of the Annual Students Symposium was held in the academic year 1987-88. The novel initiative was formulated by Gouthama, presently a faculty member at IIT Kanpur. Traditionally the aim, with which this event was envisaged, was to create a platform for the students of this department to interact by presenting and sharing their research amongst themselves. With time, and with the induction of undergraduates, this event has broadened to include the new members of this department, as well as try to familiarise its students with the research done elsewhere. This year, we take pride in ourselves by maintaining the legacy of this Annual Students’ Symposium for 29 years.

Message from Convenors

Times of festivity are times to be relished. For a person married to the technical way of life, there can be nothing more joyful than the moment when he can speak about his work to an appreciative audience. This is the moment for which he waits patiently, just like one waits for the arrival of a festive season. One such moment, for which the students of this department wait every year, is the Annual Students’ Symposium. Happening for the last 28 years, the aim of this symposium has been to present a platform for the research students of this department to interact, by presenting their ideas, amongst themselves. It also doubles up its responsibilities and enlightens the students about research taking place elsewhere through talks by dignitaries invited from various academies and industries. The 29th Annual Students’ Symposium will be held on 21st and 22nd January, 2016. It gives us immense pleasure to be a part of the organising team of the students’ symposium. We hope the effort that we put in bears fruit through a successful conduction of the symposium, and may this symposium be a pleasurable moment for the students of the department as well.

Convenors,

Devi Lal

Vinci Mojamdar