faculty

John Michael Collins

Professor of Physics, Chair of Physics and Astronomy

Departments

Physics and Astronomy

Programs

Physics

Contact

Diana Davis Spencer Discovery Center, Room 1334

(508) 286-3976

About

Main Interests

Physics, especially the interaction of radiation with matter; the role of science in society, politics, sports (basketball, bicycling, golf), and family.

I enjoy teaching Physics at all levels. My most recent teaching interest is in transforming the Introductory Physics courses from a lecture-based course to a combined lab/lecture format. This new format provides students with the opportunity to gain immediate insights, through experimentation, of the material being presented in class. The format seeks to have students actively engaged in learning for the entire class, and is based on the TEAL teaching format developed in part at MIT.

As an experimental physicist, I am especially interested in providing students with meaningful laboratory experiences, from the introductory course to the senior thesis projects.

Courses taught include Introductory Physics I and II, Modern Physics I and II, Optics, Classical Mechanics, Electricity and Magnetism, Statistical Physics, Quantum Physics, Experimental Physics, The Physics of Music and Sound, and Electronic Circuits.

Degrees

Ph.D. and M.A. in Physics, Boston College
B.A. in Physics, College of the Holy Cross

Research Interests

My main field of interest is the luminescence spectroscopy of solids. The Laser Spectroscopy Group at Wheaton investigates primarily the luminescent properties of solid state laser materials and phosphors used for lighting and display screens, among other applications. The materials of our focus are rare earth ion- and transition metal ion-doped insulators. After absorbing energy, these materials emit light that is characteristic of the atoms that make up the solid. Usually, part of the absorbed energy is converted into heat instead of light, which results in less light being emitted. We investigate the processes that take place following the absorption of light. These processes include radiative decay (luminescence), non-radiative decay (conversion of energy to heat), energy transfer between ions, upconversion, and charge transfer.

Our experimental efforts are focused in the following areas:
The optical properties of oxides materials with metal-metal charge transfer states for potential application in solid state lighting devices

  • Luminescent properties of nanoparticles doped with rare earth or transition metal ions, with particular attention to the effects of confinement on non-radiative properties
  • Plasmonics: The enhancement or suppression of luminescence from ions/molecules near metallic surfaces, and the interaction between the ion/molecule and the “surface plasmons” of the metal.
  • The temperature dependence of non-radiative processes, including (1) multiphonon decay, (2) energy transfer, and (3) concentration quenching.

Theory/Modeling

While in experimental physics we seek gain insights into the behavior of a system using direct measurements, as physicists we also strive to understand that behavior, that is, to explain why systems behave the way they do. Thus, in parallel with the experimental work we do in the lab, we also investigate our luminescent systems using theoretical tools and computer modeling in order to compare theoretical predictions with experimental results. The goal is to develop theoretical tools and computational methods that will make is easier for other workers in the field to interpret their results. A larger goal is to develop a model of these luminescent systems that might provide some predictive value, making clear the constraints that lead to highly-efficient luminescent systems.

Teaching Interests

I enjoy teaching Physics at all levels. My most recent efforts involve making the Introductory Physics course more equitable and inclusive, so that all students in the class have a greater sense of belonging and a higher chance of success. The Introductory Physics is taught in a combined lab/lecture studio format. After brief lectures, students are asked to either work in group problem-solving exercises or do a lab. These activities provide students with the opportunity to gain immediate insights, through experimentation or attempting problems, of the material being presented in class. The format seeks to have students actively engaged in learning for the entire class, and is based on the TEAL (Technology-Enhanced Active Learning) teaching format developed at North Carolina State University and adapted further at MIT.

As an experimental physicist, I am especially interested in providing students with meaningful laboratory experiences, from the introductory course to the senior thesis projects.

Courses taught include Introductory Physics I and II, Modern Physics I and II, Optics, Classical Mechanics, Electricity and Magnetism, Statistical Physics, Quantum Physics, Experimental Physics, The Physics of Music and Sound, and Electronic Circuits.

Publications

Formulation of radiative and nonradiative transitions of a polyatomic system within the crude adiabatic approximation, K. C. Mishra and J. Collins, submitted for publication to the ECS Journal of Solid State Sci. Tech. (July, 2022)

Temperature dependence of nonradiative transitions of an excited optical ion in solids, K. C. Mishra and J. Collins, ECS Journal of Solid State Sci. Tech., 11, 076003 (2022) doi: https://doi.org/10.1149/2162-8777/ac7fb7

Surface plasmon-mediated decay processes of ions in solids, J. Collins and K. Mishra, “Light-Matter Interactions Towards the Nanoscale” NATO Science for Peace and Security Series B: Physics and Biophysics, (2022) Book chapter, doi: 10.1007/978-94-024-2138-5_2 (2022)

“Light-Matter Interactions Towards the Nanoscale”, NATO Science for Peace and Security Series B: Physics and Biophysics”, Springer, Eds. M Cesaria, A. Cala Lesina, and J. Collins, (2022) ISSN: 18746535 18746500

Theory of nonradiative energy transfer between two optical ons using proper adiabatic approximation, K. C. Mishra and J. Collins, ECS Journal of Solid State Sci. Tech., 10, 066003 (2021).

First-principles calculations of charge transfer transitions of Eu3+ in Y2O3 and Y2O2S, S. Takemura, K. C. Mishra, J. Collins, and K. Ogasawara, ECS Journal of Solid State Sci. Tech., 9, 066005 (2020).

Revisiting the theory of radiative and nonradiative transitions of a polyatomic system, K. C. Mishra and J. Collins, ECS J. Solid State Sci. Technol., 9 ,066004 (2020).

A First-Principles investigation of the crystal-field and Racah parameters of transition metal ions: Cr3+ in alumina, K. Ogasawara, K. C. Mishra and J. Collins, ECS Journal of Solid State Sci. Tech., 9, 016011 (2020).

Wavelength-Selective Nonlinear Imaging and Photo-Induced Cell Damage by Dielectric Harmonic Nanoparticles, V. Kilin, G. Campargue, I. Fureraj, S. Sakong, T. Sabri, F. Riporto, A. Vieren, Y. Mugnier, C. Mas, D. Staedler, J. Collins, L. Bonacina, A. Vogel, J. A. Capobianco, and J-P Wolf, ACS Nano, 14 (4), 4087-4095, (2020) doi: 10.1021/acsnano.9b08813.

Investigation of Purcell factor for an activator ion due to surface plasmon modes, J. Collins and K. C. Mishra, ECS Journal of Solid State Sci. Tech. 9, 016002 (2020)

Dipole-dipole non-radiative energy transfer mediated by surface plasmons on a metallic interface, K. C. Mishra and J. Collins, ECS J. Solid State Sci. Tech. 8, R27 (2019).

Theory of radiative lifetime of an activator ion due to surface plasmons, K.C. Mishra, J. Collins and A. Piquette, ECS J. Solid State Sci. Tech. 7, R42 (2018).

A quantum electrodynamics formulation of energy transfer between two optically active ions, K. C. Mishra and J. Collins, ECS J. Solid State Sci. Tech. 7, R1 (2018).

Broadband, white light emission from doped and undoped insulators, S. Tabanli, H. Cinkaya Yilmaz, G. Bilir, M. Erdem, G. Eryurek, B. Di Bartolo, and J. Collins, ECS J. Solid State Sci. Tech. 7 (1) (2018) R3199-R3210; doi:10.1149/2.0261801jss

Emission of white-light in cubic Y4Zr3O12:Yb3+ induced by a continuous infrared laser, F. Gonzalez, R. Khadka, R. López-Juárez, J. Collins, and B. Di Bartolo, J. Luminescence 198, 320-326 (2018)

Structural, mechanical, thermal and optical properties of Yb, Pr,-doped Y4Zr3O12 ceramics, F. González, R. López-Juárez, H.D. Orozco-Hernández,  J. Zarate-Medina, R. Khadka, J. Collins, and B. Di Bartolo, Ceramics International, 15, 17681-17687 (2018) https://doi.org/10.1016/j.ceramint.2018.06.232

Non-radiative processes in nanocrystals, J. Collins, in “Quantum Nano-Photonics”, NATO Science for Peace and Security Series B: Physics and Biophysics, Springer (2017) doi: 10.1007/978-94-024-0850-8_4

Spectral characterization and white light generation by yttrium silicate nanopowders undoped and doped with ytterbium(III) at different concentrations when excited with a diode laser at 975 nm, H. Cinkaya, G. Eryurek, G. Bilir, J.Collins, and B. Di Bartolo, Optical Materials, 63, 167-172 (2017) doi: 10.1016/j.optmat.2016.06.05

On the efficient warm white light emission from nanosized Y2O3, M. Cesaria, J. Collins, and B. Di Bartolo, Journal of Luminescence 169, 574-580 (2016) doi: 10.1016/j.jlumin.2015.08.017

Presentations

J. Collins, K. Mishra, and B. Osborn, (Invited talk) Temperature Dependence of Nonradiative Transitions of an Excited Optical Ion in Solids Using the Proper Adiabatic Approximation, to be presented at the 242nd ECS Meeting of the Electrochemical Society, Atlanta, GA, October 9 – 13, 2022.

J. Collins and K. Mishra, Theory of Nonradiative Energy Transfer between Two Optical Ions Using the Proper Adiabatic Approximation, presented (virtually) at the 240th ECS Meeting of the Electrochemical Society, Orlando, FL, October 10-14, 2021.

J. Collins, N. Sundstrom, and K. Mishra, Monte-Carlo Modeling of Plasmon-Mediated Ion-Ion Energy Transfer, presented (virtually) at the 238th meeting of the Electrochemical Society, Honolulu, HI, October 13-17, 2020.

J. Collins and K. Mishra, Revisiting the theory of vibronic transitions in solids, presented (virtually) at the 238th meeting of the Electrochemical Society, Honolulu, HI, October 13-17, 2020.

J. Collins and K. Mishra, Electric Dipole-Electric Dipole Non-Radiative Energy Transfer Mediated by Surface Plasmons on a Metal Surface, Invited talk, presented (virtually) at the 238th meeting of the Electrochemical Society, Atlanta, GA, October 14, 2019.

J. Collins and K. Mishra, Surface plasmon-mediated decay processes of ions in solids, a series four lectures presented at the International School of Atomic and Molecular Spectroscopy, Light-Matter Interactions towards the Nanoscale, Erice, Sicily, Italy, July 4 – 19, 201

J. Collins, K. Mishra and A. Piquette, Theory of radiative lifetime for activator ions due to surface plasmons, presented at the AiMES Conference of the Electrochemical Society, Cancun, Mexico, September 30 – October 4, 2018.

J. Collins, K. Mishra and A. Piquette, Theory of radiative lifetime for activator ions due to surface plasmons, presented at the International School of Atomic and Molecular Spectroscopy, Workshop on Recent Developments in Luminescent Materials, Erice, Sicily, Italy, July 25 – 31, 2018

J. Collins, Nonradiative processes in crystals and nanocrystals, two lectures presented at the International School of Atomic and Molecular Spectroscopy, Quantum Nanophotonics, Erice, Sicily, Italy, July 20 – August 4, 2017

Student Projects

Students of all class years are welcome to work in the Laser Lab. The only prerequisite is an interest in physics. The lab is generally busy both during the academic year and the summer. Some of the projects that students get involved in are:

    • Building and characterizing lasers
    • Taking spectroscopic measurements on solids (single crystals, powders, or glasses)
    • Computer modeling of solids to compare with experimental data (using matlab, python, or whatever language you prefer…)
    • Testing, calibrating, or automating equipment.

In all of these projects, students are guided from the novice stage to the point where they can train other students. For each person working in the lab, we expect that they:

    • come to understand the key pieces of equipment in the lab, and how each works,
    • become proficient in taking different types of measurements,
    • show the ability to work independently and make day-to-day decisions about their project,
    • understand the underlying physics of the systems that they are investigating,
    • gain the knowledge necessary to do the data analysis, plot results, etc., and
    • learn how to keep lab notes.

Below are some student honors thesis projects that I have overseen.

Ben Osborn, (22) Thermal Quenching of Luminescence in YAG:Ce
Calvin Riiska, (20) Sub-Diffraction Limited Spectroscopy with Fluorescent Nanoparticles
Becky Johnson (11) Perceived Mathematics Self-efficacy in Introductory Physics
Tyler Bennett, (11) Luminescence and Kinetic Studies of Praseodymium-Doped Lithium Niobate
Alex Shvonski (08) Time Series Analysis of the Optical and Radio Variability of BL LAC
Jessica Tolson (07) Energy Transfer Processes in Yttrium Silicate
Nick Roberts-Warren (07) Group Theoretical Techniques in Analyzing Vibronic Transitions in Doped Crystals
Chris Steutzle (07) Computer Modeling and Visualization of Luminescent Crystals: The Role of Energy Transfer Upconversion
Jon McBee (04) Modeling of Delta Scudi Pulsating Stars
Ken Bycenski (01) Power and Temperature Dependence of Non-Radiative Decay in Er:Glass
B.J. Hansz (99) Coherent Transient Laser Spectroscopy: Light Shifts of Rare-Earth Ions in Solids
Jessica Krick (99) Two Stars Passing in the Night: An Analysis of Eclipsing Binary Systems
Adam Petri (98) Thermal Effects on Upconversion Dynamics of Er in YLF4 and Fluoride Glass
Jim Phillips (98) Construction and Characterization of a Q-Switched Nd:YAG Laser
Tara Healey (96) Theoretical and Experimental Investigations of Solid State Laser Systems