## Professor

#### Graduate Program Coordinator

Department of Physics

University of Windsor

401 Sunset Avenue

Windsor, Ontario, N9B 3P4, Canada

(519) 253-3000 x2662

Fax: (519) 973-7075

Room 277-3 Essex Hall

rangan@uwindsor.ca

## Professional Associations

- PI, Ontario Physics Education Network
- Member, Evaluation Committee, NSERC Research Tools and Instruments grants, 2018
- Chair, Steering Committee for International Day of Light, Canada 2018
- Secretary-Treasurer, Division of Physics Education, Canadian Association of Physicists (2017-2019)
- Secretary-Treasurer, Committee to Encourage Women in Physics, Canadian Association of Physicists (2018-2019)
- Founder of Promoters of Experiential and Active, Research-based Learning, A Community of Practice

## Affiliations

- BiopSys - NSERC Strategic Network on Bioplasmonic Systems
- Mathematics of Information Technology and Complex Systems - Network of Centers of Excellence. Project website
- Department of Physics, The University of Michigan, Visiting Associate Professor, 2006-date
- Michigan Center for Theoretical Physics - Associate Member 2006-2015

## Research Interest & Expertise

Control of nanoscale light-matter interactions: theory and computation. See research page for projects and opportunities.

### Graduate opportunity

I have an opening for a graduate student who is interested in working on projects described below. My research projects require techniques from many areas: coherent control, quantum optics, atomic molecular and optical (AMO) physics, nanoplasmonics, nanophotonics, and health research. Students I seek will have:

- a strong background (= coursework & A grades) in quantum mechanics and electromagnetic theory
- a minimum GPA of A- (80% and above)
- some prior research experience & familiarity with a programming language

Interested? Email me with a paragraph on why you want to work in my group. Review this article for tips on what to write (and what not to write). I look forward to hearing from you. (FYI: I will not reply to mass emails or emails that begin with "Dear Sir")

### Control of nanoscale light-matter interactions: Theory and Computation

My group studies the interaction between light and matter at the nanoscale (atoms, molecules, nanostructures), the control of this interaction, and investigates its possible applications. We develop theoretical and computational methods for modeling quantum and classical dynamics in atoms, ions and nanostructures.

### Quantum control

The focus of this research is to discover and design electromagnetic fields that will control atoms, molecules and nanostructures to perform quantum operations. Our research goal is to create new schemes of quantum control with electromagnetic fields (cw or pulses) both in atomic systems (such as trapped ions and Rydberg atoms), and in many-body systems (such as metal nanostructures). ($$: NSERC, CFI, ORF)

Quantum control is very important for developing theories in chemical dynamics, quantum information science and quantum state engineering. We developed the first method for the optimal control of an algorithm that has been used for quantum computing in multi-level systems. Recently, mathematicians Tony Bloch, Roger Brockett and I have provided explicit dense subspace controllability results for an infinite-dimensional quantum system (trapped-ion). This work expands the scope of quantum control research to beyond that of finite-dimensional quantum systems. We are currently interested in quantum control in the presence of decoherence and/or metal nanostructures ($$: NSERC)

### Nanoplasmonics and biosensors

Nanoplasmonics is an exciting area of fundamental research, which also has the promise of leading to important applications. Plasmonic nanodevices are expected to significantly advance many areas of research such as diffraction-limited nano-optics, sensing, clinical diagnostics, nanoelectronics, to mention a few. In my research program, we are focusing on developing bio-chemo sensors, in order to develop improved nanodevices for clinical diagnostics. ($$: NSERC, CFI, ORF, Ontario Association of Medical Laboratories, CIPI, Ontario Centres of Excellence)

### Optimization & Health research (completed project)

Optimization methods developed for controlling light-matter interactions can be applied to solve large optimization problems in medical research. In collaboration with Jeff Richer at the Windsor Regional Cancer Center, we are trying to find optimal radiation treatment planning protocols using the learning algorithm. ($$: Windsor Regional Cancer Centre, MITACS)

## Publications

- C. S. DiLoreto and C. Rangan, 2018, Single-particle model of a strongly driven, dense, nanoscale quantum ensemble, Physical Review A, v. 97, p. 013812.
- Rooney, Patrick; Bloch, Anthony, M; Rangan, Chitra, 2018, Steering the Eigenvalues of the Density Operator in Hamiltonian-Controlled Quantum Lindblad Systems, IEEE Transactions on Automatic Control, v. 63, pp. 672 - 681.
- C. S. DiLoreto and C. Rangan, 2017, Polarization control of spontaneous emission for rapid quantum state initialization, Physical Review A, v. 95, p.043834. .
- Rooney, Patrick; Bloch, Anthony, M; Rangan, Chitra, 2016, Flag-based control of quantum purity for n=2 systems, Physical Review A, v. 93, pp. 063424.
- T. Cheng, C. Rangan, and J.E. Sipe, 2013, Metallic nanoparticles on waveguide structures: Effects on waveguide mode properties, and the promise of sensing applications, Journal of the Optical Society of America B, v. 30, pp. 743–765. [pdf] Erratum: 2014, Journal of the Optical Society of America B, v. 31, pp. 2845-2845.
- A.M. Bloch, R.W. Brockett, and C. Rangan, 2010, Finite Controllability of Infinite-Dimensional Quantum Systems, IEEE Transactions on Automatic Control, v. 55, pp.1797-1805. [pdf]
- S.M. Hashemi Rafsanjani, T. Cheng, S. Mittler, C. Rangan, 2010, “A novel measure of refractive index sensitivity in nanoplasmonic biosensors”, Journal of Applied Physics, v. 107, art. no. 094303. [pdf]
- Invited brief review: C. Rangan, 2009, “The trapped-ion qubit: Coherent control in infinite-dimensional quantum systems”, Modern Physics Letters A, vol. 24, pp. 2565-2578. [pdf]
- S. Durocher, A. Rezaee, Bulent Mutus, Silvia Mittler, C. Rangan, 2008, “A gold-nanoparticle based reagent for sizing small molecular weight thiols”, Journal of the American Chemical Society, v. 131, pp. 2475-2477. [pdf]
- Patrick Rooney, Songbo Xu, Asad Rezaee, Touraj Manifar, Abdollah Hassanzadeh, Ganna Podoprygorina, Volker Boehmer, Chitra Rangan, and Silvia Mittler, 2008, "Control of surface plasmon resonances in dielectrically-coated proximate gold nanoparticles immobilized on a substrate", Physical Review B, v. 77, art. no. 235446. [pdf]
- L.H. Pedersen, C. Rangan, 2007, “Controllability and universal three-qubit quantum computation with trapped-electron quantum states”, Quantum Information Processing, v. 7, pp. 33-42. [pdf]
- Songbo Xu, Ganna Podoprygorina, Volker Böhmer, Ziheng Ding, Patrick Rooney, C. Rangan and Silvia Mittler, 2007, "Tetraurea calix[4]arenes with Sulfur Functions: Synthesis, Dimerization to Capsules and Self-Assembly on Gold", Organic and Biomolecular Chemistry, v. 5, pp. 558–568. [pdf]
- R. Cabrera, C. Rangan, and W.E. Baylis, 2007, “Sufficient condition for the control of n-qubit systems”, Physical Review A, v. 76, art. no. 33401. [pdf]
- J. M. Murray, S.N. Pisharody, H. Wen, C. Rangan, P.H. Bucksbaum, 2006, “Information hiding and retrieval in Rydberg wave packets using half-cycle pulses”, Physical Review A, v. 74, art. no. 43402. [pdf]
- C. Rangan and R.J.A. Murray, 2005, “Theory of detection of angular momentum states in Rydberg atoms using half-cycle pulses”, Physical Review A, v. 72, art. no. 053409. [pdf]
- C. Rangan and A.M. Bloch, 2005, “Control of finite-dimensional quantum systems: application to a spin-half particle coupled with a finite quantum harmonic oscillator”, Journal of Mathematical Physics, v. 46, art. no. 32106. [pdf]
- C. Rangan, A.M. Bloch, C.R. Monroe, and P.H. Bucksbaum. “Control of trapped-ion quantum states with optical pulses”, Physical Review Letters, v. 92, art. no.113004 (2004). [pdf]
- H. Wen, C. Rangan, and P.H. Bucksbaum. “Control of angular momentum evolution in Stark wave packets”, Physical Review A v. 68, art. no. 53405 (2003). [pdf]
- John P. Boyd, C. Rangan and P.H. Bucksbaum. “Pseudospectral methods on a semi-infinite interval with application to the hydrogen atom: a comparison of the mapped Fourier-sine method with Laguerre series and Rational Chebyshev expansions”, Journal of Computational Physics, 188, 56 (2003). [pdf]
- C. Rangan, J. Ahn, D.N. Hutchinson and P.H. Bucksbaum. “Control of Rydberg atoms for performing Grover’s search algorithm”, Journal of Modern Optics, 49, 2339 (2002). [pdf]
- J. Ahn, C. Rangan, D.N. Hutchinson and P.H. Bucksbaum. “Quantum state information retrieval in a Rydberg atom data register”, Physical Review A 66, 22312 (2002). [pdf]
- C. Rangan and P.H. Bucksbaum. “Optimally shaped terahertz pulses for a quantum algorithm on a Rydberg atom data register”, Physical Review A 64, 33417 (2001). [pdf]
- A.R.P. Rau and C. Rangan. Reply to ‘Comment on “Photodetachment in combined static and dynamic electric fields” ’, Physical Review A 64, 37402 (2001). [pdf]
- J. Ahn, C. Rangan, D.N. Hutchinson, and P.H. Bucksbaum. “Quantum phase retrieval of a Rydberg wave packet using a half-cycle pulse”, Physical Review Letters 86, 1179 (2001). [pdf]
- C. Rangan, K.J. Schafer and A.R.P. Rau. “Dynamics of diamagnetic Zeeman states ionized by half-cycle pulses”, Physical Review A 61, 53410 (2000). [pdf]
- C. Rangan and A.R.P. Rau. “Photodetachment in combined static and dynamic electric fields”, Physical Review A 61, 33405 (2000). [pdf]

- "The Controllability of Infinite Quantum Systems" by Roger W. Brockett, C. Rangan and Anthony M. Bloch, The 42nd IEEE Conference on Decision and Control, December 2003 (invited paper). [pdf]
- "Effect of third-order non-linearity on squeezed solitons in optical fibers" by C. Rangan, M.V. Satyanarayana, B.M. Sivaram, Physics and Simulation of Optoelectronic Devices II (SPIE Proceedings Vol. 2146), Eds. Weng W. Chow and Marek A. Osinski, p. 448-456, SPIE, Washington, 1994.

- Book chapter: D.A. Travo, R. Huang, T. Cheng, C. Rangan and E. Ertorter, S. Mittler, 2013, “Experimental and Theoretical Issues of Nanoplasmonics in Medicine”, Applications of Electrochemistry in Medicine, Ed. Mordechay Schlesinger, Modern Aspects of Electrochemistry v.56, pp. 343-379, Springer, New York. [pdf]
- Book chapter: C. Rangan, 2009, “Symmetry considerations in the modeling of nanoscale light-matter interactions”, Modeling and Numerical Simulations II, Ed. Mordechay Schlesinger, Modern Aspects of Electrochemistry, v. 44, pp.113-130, Springer, New York. [pdf]
- "The propagation of squeezed solitons in optical fibers - third order dispersion effects", C. Rangan, M.V. Satyanarayana and B.M. Sivaram, in Perspectives in theoretical nuclear physics, p. 234-241, Wiley-Eastern Ltd., New Delhi, 1994.

- "Optical properties of gold nanoparticles on surfaces: applications to biosensing", AMO seminar, Physics Department, University of Michigan, Ann Arbor, MI. October 2007.
- "Nanoplasmonics and its applications in biomedicine", Colloquium, Physics Department, Miami University, Oxford, OH. October 2007.
- “Coherent Control of Infinite-dimensional Quantum Systems”, DAMOP 07, Annual Meeting of the Division of Atomic, Molecular and Optical Physics, American Physical Society, Calgary, AB. June 2007.
- “Controllability and information processing in infinite-dimensional quantum systems”, PRACQSYS 2006: The Principles and Applications of Control in Quantum Systems, Harvard University, Cambridge, MA. August 2006.
- “64-496: A multi-genre, collaborative course on technical communication for physicists”, Engaging the 21st Century student: regional conference on teaching and learning, University of Windsor. April 2006.
- “Quantum Information Processing and Terahertz Control in Rydberg Atoms”, Seminar, Physics Department, University of Waterloo, Waterloo, ON. November 2005.
- “Introduction to quantum computing”, Tutorial Lecture, School of Computer Science, University of Windsor. October 2005.
- “Quantum computing with atoms”, Colloquium, Department of Physics, University of Western Ontario, London, ON. October 2005.
- “Quantum information processing in atomic systems”, Department of Physics, Indian Institute of Technology, Chennai, India. September 2005.
- "Coherent control and quantum information processing in atomic systems", 2005 Gordon Conference on Quantum Control of Light and Matter, Colby College, Waterville, ME, August 2005.
- “Coherent control and quantum information processing with Rydberg atoms”, 2005 Congress of the Canadian Association of Physicists, University of British Columbia, Vancouver, BC, June 2005.
- “Coherent control and quantum information processing with Rydberg atoms and trapped ions”, Workshop on Building Computational Devices using Coherent Control, The University of Michigan, Ann Arbor, MI, June 2004.
- “Quantum Computing”, Physics Education Workshop, University of Windsor, Windsor, ON, April 2004.
- “On our way to the emerald city: quantum computing”, Department of Physics, Colby College, Waterville, ME, October 2003.
- “Quantum Information Processing: computing with atoms using light”, Department of Physics, University of Windsor, Windsor, ON, Canada, October 2003.
- “Terahertz control of Rydberg atoms: applications to quantum information processing”, Chemistry Department, Massachusetts Institute of Technology, Cambridge, MA, July 2003.
- “Quantum control and quantum information processing”, AMO seminar, Institute for Theoretical Atomic, Molecular and Optical Physics, Harvard-Smithsonian Center for Astrophysics, Cambridge, MA, January 2003.
- “Quantum information and quantum computing”, Research seminar, College of Engineering and Computer Science, The University of Michigan-Dearborn, Dearborn, MI, January 2003.
- “Quantum control and quantum information processing”, Seminar, Center for Ultrafast Optical Sciences, University of Michigan, Ann Arbor, MI, November 2002.
- “Quantum search algorithm in a Rydberg atom”, Colloquium, Department of Physics, Oakland University, Rochester, MI, October 2002.
- “Quantum search with Rydberg atoms”, Colloquium, Department of Physics, Western Michigan University, Kalamazoo, MI, September 2002.
- "Performing Grover's search algorithm on a Rydberg atom data register", XXXII Winter Colloquium on the Physics of Quantum Electronics, Snowbird, UT, January 2002.
- "Optimal control of Rydberg Atoms", AMO seminar, Department of Physics, University of Michigan, Ann Arbor, October 2001.
- "Phase retrieval on a Rydberg atom data register through optimally shaped terahertz pulses", 3rd Annual Cross Border Workshop on Laser Science, University of Toronto, Canada, May 2001.
- "Performing a quantum algorithm on a Rydberg atom through optimally shaped terahertz pulses", Institute of Mathematical Sciences, Chennai, India, April 2001.
- "Rydberg atoms in strong magnetic fields: Probing them with terahertz half-cycle pulses", Department of Physics, Indian Institute of Technology (Madras), Chennai, India, April 2001.

- "Ionization of Diamagnetic Zeeman States by Half-Cycle Pulses", May 2000. Department of Physics and Astronomy, Louisiana State University, LA 70803. Advisors: Ravi Rau and Ken Schafer
- Master's thesis: "Propagation of Squeezed Solitons in Optical Fibers", July 1993. Department of Physics, Indian Institute of Technology, Madras, India. Advisors: M.V. Satyanarayana and B.M. Sivaram