Excerpts of my work and publications are listed below.

PhD Thesis

I have defended my PhD thesis on Monday 7th October 2013, and received the PhD on October 14th. The title is 

"Photothermal Single Particle Detection in Theory & Experiments".

 

The thesis gives a complete account of the photothermal signal of single particles in transmission-type photothermal microscopes. It consistently combines various theoretical approaches and gives several applications and experimental proof-of-principles. You may find it:

 

published online, downloadable as a .pdf-file.

Articles in preparation

  • "Revisiting the round bottom flask rainbow experiment", M. Selmke and S. Selmke, submitted, available on arXiv.org
  • "Theory of Photon Nudging I: Directed Transport", M. Selmke, U. Khadka, A. Bregulla, F. Chichos and H. Yang, to be submitted to Phys. Chem. Chem. Phys.
  • "Theory of Photon Nudging II: Positional Statistics", M. Selmke, U. Khadka, A. Bregulla, F. Chichos and H. Yang, to be submitted to Phys. Chem. Chem. Phys.
  • 3 more articles

Journal Articles

Some of the articles can be found as a downloadable .pdf on the groups homepage under publications.

"Thermal Diffusivities Studied by Single-Particle Photothermal Deflection Microscopy", A. Heber, M. Selmke, and F. CichosACS Photonics, 2017.

 

This article discusses the application of the Photothermal Rutherford Deflection technique to the measurement of thermal diffusivities. In particular, deflection resonances caused by the pseudo-wave of the nano-scopic refractive index lens are probed as predicted by the theory outlined earlier in "Photothermal single particle microscopy using a single laser beam", Applied Physics Letters (Appl. Phys. Lett.).

"Artificial Circumzenithal and Circumhorizontal Arcs", M. Selmke and S. Selmke, accepted at the American Journal of Physics (Am. J. Phys.)

arXiv.org > Physics > Atmospheric and Oceanic Physics > arXiv:1608.08664

 

We describe a simple set of experiments which use a glass of water only. We show that they reproduce the circumzenithal, circumhorizontal and suncave Parry arcs, see the physics at home section. Although the experiment itself has been known at least since 1920 (see "Gilbert light experiments for boys", p. 98, Experiment No. 94), or the numerous google search results for "glass water table rainbow", it has often been put in the wrong context of a rainbow.

 

We re-derive the main characteristics of the observed natural and artificial phenomena.

"Complex artificial halos for the classroom", American Journal of Physics (Am. J. Phys.), Vol. 84(7), 561-564, M. Selmke and S. Selmke2016.

 

The article describes the construction and operation of a small modular halo machine (see physics at home section) and how to use it to generate artificial Lowitz-, tangential /circumscribed, Parry halos and (sub-)parhelias / the parhelic circle. Finally, a method of generating complex composite displays is described, and how to emulate the sky sphere. (Note: we used a 20mW blue laser diode)

 

see also the BoredPanda.com article.

Selmke2016_AJP_HaloMachines.pdf
Adobe Acrobat Dokument 1.5 MB

"The physics of the photothermal detection of single absorbing nano-objects: a review", ArXiv, M. Selmke and F. Cichos, 2015. (to be submitted)

 

A comprehensive review of the existing models on the photothermal signal generation mechanism, including new results on the signal modification above interfaces.

"Intensity distribution of the parhelic circle and embedded parhelia at zero solar elevation: theory and experiments", Applied Optics (Appl. Opt.), Vol. 54, Issue 22, 6608-6615, S. Borchardt and M. Selmke2015.
The article disseminates the parhelic circle (PHC) halo intensity distribution at zero solar elevation. Various azimuthal positions of characteristic features (Liljequist PH, 120° PH, 90° PH of 1st and 2nd order, round trip halos, blue edges) are given and compared to experimental data obtained using a rotating BK7 glass prism. Finite solar elevations may be incorporated using Bravais' index of refraction for inclined rays, see the article "Artificial Halos".
Borchardt_ao-54-22-6608.pdf
Adobe Acrobat Dokument 1.3 MB

"Artificial Halos", American Journal of Physics (Am. J. Phys.), Vol. 83(9), 751-760, M. Selmke2015.

 

The article gives an introduction to ice halos and describes various experiments which artificially generate certain halos using a glass prism commercially available through Edmund Optics. Artificial Parhelic Circles and various Parhelia along with responsible ray paths are discussed in detail.

A Figure of the article was chosen for the cover image of the September issue in which the article is published. The image shows an illuminated  transparent acrylic juggle ball with its corresponding caustic and an illuminated hexagonal BK7 glass prism with vividly colored columns of light emerging from it.

 

 

The halo articles were covered in a University Press article. It has been reproduced on the Faculty homepage, and various other news sources online such as myscience.deinnovations-report.deinformationsdienst Wissenschaftpro-physik.de. The article appeared in the Leipziger Volkszeitung / LVZ, issue 01/09/2015, page 15, see article in the LVZ online archive. It also  appeared printed in the magazine "Liebigstraße aktuell", issue 18/2015.

Selmke2015_AmJPhys_ArtificialHalos.pdf
Adobe Acrobat Dokument 2.9 MB

"Hot Brownian motion and photophoretic self-propulsion", diffusion-fundamentals.org Vol. 23(1), 1-19, R. Schachoff, M. Selmke, A. Bregulla, F. Cichos, D. Rings, D. Chakraborty, K. Kroy, K. Günther, A. Henning-Knechtel, E. Sperling, M. Mertig2015.

 

Article summarizing the progress within the SFG Research Unit FOR 877, "From Local Constraints to Macroscopic Transport". It covers hot Brownian motion, photothermal correlation spectroscopy and microscopy as well as artificial swimmers, amongst other topics.

"Thermal diffusivity measured with a single plasmonic nanoparticle", Physical Chemistry Chemical Physics (PCCP), accepted, A. Heber, M. Selmke, F. Cichos, 2015.

 

This article presents measurements of thermal diffusivities of liquids and solids based upon frequency-dependent photothermal microscopy. See also [Appl. Phys. Lett. 105, 0135011, M. Selmke et al., 2014].

"Mie scattering by a refractive 1/r inhomogeneity: electromagnetic scattering by the infinite Coulomb-like scatterer", Journal of Quantitative Spectroscopy & Radiative Transfer (JQSRT, special issue on accompanying the LIP2014 conference), 162, 175-183, M. Selmke, 2015.

 

This is a theoretical study of the plane wave scattering characteristics for weak electromagnetic scattering by a 1/r refractive index inhomogeneity. Shaped beams are shown to resolve the divergences known from Coulomb scattering.

"Comment on: "Optimal detection angle in sub-diffraction resolution photothermal microscopy: application for high sensitivity imaging of biological tissues""Optics Express (Opt. Express) Vol. 23, Issue 5, p. 6747-6750, M. Selmke and F. Cichos, 2015 (republished: Virtual Journal for Biomedical Optics, Vol. 10, Issue 4, 2015)

 

This comment points out several fundamental misconceptions in the theoretical treatment of the photothermal signal as done in the article [Opt. Express, Vol. 22, Issue 16, p. 18833–18842, Miyazaki et al.,2014]. 

The reply to the comment, [Opt. Express, Miyazaki et al., Vol. 23, Issue 5, p. 6751-6753, 2015], suggests that the weakness of the scattering resolves the inconsistencies. This is not accurate and misses the points raised in the original comment.

"Photothermal single particle microscopy using a single laser beam", Applied Physics Letters (Appl. Phys. Lett.), Vol. 105, 0135011, M. Selmke, A. Heber, M. Braun, F. Cichos, 2014

 

The article introduces a variant of photothermal microscopy for which only a single laser beam is necessary. The method rests on a detailed understanding of the frequency-dependence and phase of the signal.

"Energy-Redistribution Signitarures in Transmission microscopy of Rayleigh and Mie particles", Journal of the Optical Society of America A (JOSA A), Vol. 31, No. 11, pp 2370-2384, M. Selmke and F. Cichos, 2014 (republished in the Virtual Journal for Biomedical Optics, Vol. 9, Issue 13, 2014)

 

This article describes in detail the interaction of a focused beam with a spherical particle of arbitrary size and refractive index. Particularly, the transmitted power is considered. The special case of small Rayleigh-paticles gives an extension of the optical theorem and provides useful expressions for photothermal microscopy and high frequencies.

"Metal nanoparticle based all-optical photothermal modulator", ACS Nano, Vol. 8, No. 2, pp 1893-1898, A. Heber, M. Selmke, F. Cichos, 2013

 


The article describes how the photothermal effect may be utilized to modulate light by light without non-linearities. Driving a liquid-crystalline first-order phase transition allows to modulate the probe beam effectively via the dissipative heating of a gold nanoparticle using a heating laser.

"Photothermal single particle Rutherford scattering microscopy", Physical Review Letters, (Phys. Rev. Lett.), Vol. 110, 103901, M. Selmke, F. Cichos, 2013

 

The letter-format short article presents a new interpretation and detection scheme in transmission photothermal detection based on an optical analogon to quantum mechanical Coulomb / Rutherford scattering of matter wave-packets.

The article was promoted by the editors of the journal and carries the label "editors suggestion".

"Photonic Rutherford Scattering: A Classical and Quantum mechanical analogy in Ray- and Wave-optics", American Journal of Physics (Am. J. Phys.), Vol. 81, No. 6, pp 405-413, M. Selmke and F. Cichos2013

 

This padagogical article explores the analogy between the optical scattering by a thermal lens and the particle scattering from a Coulomb potential. The analogy is discussed in the high and low energy limit.

An image from the supplementary media files to the article was chosen as the cover figure for the issue of the Amercian Journal of Physics

The supplementary files are free and can be found uder "Article Objects (20)" → "Supplementary Files (EPAPS)"

Download the article as a .pdf-file
Selmke2013_AJP.pdf
Adobe Acrobat Dokument 3.4 MB

"Photothermal Signal Distribution Analysis (PhoSDA)", Physical Chemistry Chemical Physics (PCCP), Vol. 15, pp. 4250-4257, M. Selmke, R. Schachoff, M. Braun, F. Cichos, 2013 (advance article)

 

In this methodological article the signal statistics for the photothermal signal are discussed for solutions of absorbing nano-particles.

"Twin-Focus Photothermal Correlation Spectroscopy", RSC Advances (RSC Adv.), Vol. 3, pp. 394-400, M. Selmke, R. Schachoff, M. Braun, F. Cichos, 2013

 

A methodological article on the correlation spectroscopy of diffusing particles detected by photothermal microscopy. It specifically used the novel twin-focus split detection volume.

"Gaussian Beam Photothermal Single Particle Microscopy" (oa), Journal of the Optical Society of America A (JOSA A), Vol. 29, No.10, pp. 2237-2241, M. Selmke, M. Braun, F. Cichos, 2012

 

A theoretical article developing a simple beam transformation formalism for Gaussian beams probing a thermal lens in photothermal microscopy. Analytical in nature, it allows the interpretation of the photothermal signal to originating from a lensing action.

"Nano-lens Diffraction around a Single Heated Nano Particle", Optics Express (Opt. Express), Vol. 20, No. 7, pp. 8055-8070, M. Selmke, M. Braun, F. Cichos, 2012, 

same article republished in the Virtual Journal for Biomedical Optics, Vol. 7, Iss. 52012

 

This article describes a simple model based on the solution to the paraxial Helmholtz equation (i.e. Kirchhoff-Fresnel diffraction) for a Gaussian beam scattered by a thermal lens. The photothermal signal is shown to be aperture dependent and invertable.

 

ERRATA: "Nano-lens Diffraction around a Single Heated Nano Particle: errata",Optics Express (Opt. Express), Vol. 21, No. 21, pp. 25344-25345

"Photothermal Single Particle Microscopy: Detection of a Nanolens",  ACS Nano, Vol. 6, No. 3, pp 2741–2749, M. Selmke, M. Braun, F. Cichos, 2012

 

This article gives the first theoretical and quantitative description of the photothermal signal of single absorbing nano-particles. The thermal lens is demonstrated to act as a lens and is treated in a rigorous Lorenz-Mie scattering framework including focusing with aberrations.

"Temperature dependent Single Molecule Rotational Dynamics in PMA", Physical Chemistry Chemical Physics (PCCP), Vol. 13, 1849-1856, S. Adhikari, M. Selmke and F. Cichos, 2011

 

This article gives, through experimental results compared to a new model, evidence for dynamical heterogeneity in polymers near the glass-transition temperature.

"Theory of Hot Brownian Motion", Soft Matter, Vol. 7, 3441-3452, D. Rings, M. Selmke, F. Cichos and K. Kroy2011

 

This theoretical article gives the details behind the theory of hot Brownian motion.

"Hot Brownian Motion", Physical Review Letters (Phys. Rev. Lett.), 105, 090604, D. Rings, R. Schachoff, M. Selmke, F. Cichos, K. Kroy2010

 

A letter-format short article introducing hot Brownian motion and the basic theoretical concepts describing it.

"Measuring Flow Profiles and Slip by Single Molecule Tracking Experiments in Thin Liquid Films", The Journal of Physical Chemistry C (J. Phys. Chem. C), Vol. 114 (10), pp 4479-4485,A. Schob, M. Pumpa, M. Selmke and F. Cichos, 2010

 

In this article, the diffusion characteristics of single tracked particles in a periodically sheared thin film are discussed based on experimental results and compared to theory.

Given Talks

Poster Presentations

These posters have been presented on the DPG meetings and on various symposia and international conferences (SFG, hot nanoparticles)

Miscellaneous

  • Illustrated article on BoredPanda about the Halo-Machine and the spherical projection screen experiments.
  • Episode 5 of the BBC documentary series "World's Weirdest Events" featured the same BK7 glass crystal I have used for the two publications in Am. J. Phys. and Appl. Opt. (see list above). The segment starts at around 45 mins (watch it on youtube) into the hour-long episode and shows some footage of the 22° halo and sundogs. The presenter of the show, Chris Packham (see image on the right), uses the crystal to explain the refraction aspect of the phenomenon. Unfortunately, the sundog formation explanation is misleading / faulty and suggests the alignment of plate crystals in a layer. The correct explanation can be found on www.atoptics.co.uk.


               The article appeared printed in the magazine "Liebigstraße aktuell", issue 18/2015, see image on the right.

     An article related to that press release was published in the local newspaper, i.e. the Leipziger Volkszeitung / LVZ, issue 01/09/2015, page 15,

          see article in the LVZ online archive. 

  • My image of Kelvin Helmholtz instabilities was posted on the facebook page of the Nasa's Earth Observatory.
  • Beautiful Dissertation by D. Rings on "Hot Brownian motion". It contains a detailed account for the theory of HBM and Brownian motion of colloidal particles in general. I have had the pleasure to cooperate with D.R. and K.K. on several publications.
  • A further elegant article regarding hot Brownian motion is "Generalised Einstein relation for Hot Brownian motion" by D. Chakraborty et al., European Physics Letters Vol. 96, 60009, 2011

Journal Articles (list)

published journal arcticles (peer-reviewed), oa: open access
  1. "Thermal Diffusivities Studied by Single-Particle Photothermal Deflection Microscopy", A. Heber, M. Selmke, and F. CichosACS Photonics2017
  2. "Artificial Circumzenithal and Circumhorizontal Arcs", accepted at the American Journal of Physics (Am. J. Phys.), M. Selmke and S. Selmke, 2016
  3. "Complex artificial halos for the classroom", American Journal of Physics (Am. J. Phys.), Vol. 84(7), 561-564, M. Selmke and S. Selmke, 2016
  4. "Artificial Halos", American Journal of Physics (Am. J. Phys.), Vol. 83(8), 751-760, M. Selmke2014
  5. "Intensity distribution of the parhelic circle and embedded parhelia at zero solar elevation: theory and experiments", Applied Optics (Appl. Opt.), Vol. 54, Issue 22, 6608-6615, S. Borchardt, M. Selmke2015
  6. "Hot Brownian motion and photophoretic self-propulsion", diffusion-fundamentals.org Vol. 23(1), 1-19, R. Schachoff, M. Selmke, A. Bregulla, F. Cichos, D. Rings, D. Chakraborty, K. Kroy, K. Günther, A. Henning-Knechtel, E. Sperling, M. Mertig2015
  7. "Thermal diffusivity measured with a single plasmonic nanoparticle", Physical Chemistry Chemical Physics (PCCP), accepted, A. Heber, M. Selmke, F. Cichos2015
  8. "Mie scattering by a refractive 1/r inhomogeneity: electromagnetic scattering by the infinite Coulomb-like scatterer", Journal of Quantitative Spectroscopy & Radiative Transfer (JSQRT), M. Selmke, 2014
  9. "Comment on: "Optimal detection angle in sub-diffraction resolution photothermal microscopy: application for high sensitivity imaging of biological tissues"" (oa)Optics Express (Opt. Express), Vol. 23, Issue 5, pp 6747-6750, M. Selmke and F. Cichos2015
  10. "Energy Redistribution Signitarures in Transmission microscopy of Rayleigh- and Mie- particles", Journal of the Optical Society of America A (JOSA A)M. Selmke and F. Cichos2014
  11. "Photothermal single particle microscopy using a single laser beam", Applied Physics Letters (Appl. Phys. Lett.), Vol. 105, 0135011, M. Selmke, A. Heber, M. Braun, F. Cichos, 2014
  12. "Metal nanoparticle based all-optical photothermal modulator", ACS Nano, Vol. 8, Issue 2, 1893-1898, A. Heber, M. Selmke, F. Cichos2013
  13. "Nano-lens Diffraction around a Single Heated Nano Particle: errata" (oa),Optics Express (Opt. Express), Vol. 21, No. 21, pp. 25344-25345, 2013
  14. "Photothermal single particle Rutherford scattering microscopy", Physical Review Letters, (Phys. Rev. Lett.), Vol. 110, 103901, M. Selmke, F. Cichos, 2013
  15. "Photonic Rutherford Scattering: A Classical and Quantum mechanical analogy in Ray- and Wave-optics", American Journal of Physics (Am. J. Phys.), Vol. 81, No. 6, pp 405-413, M. Selmke and F. Cichos, 2013
  16. "Photothermal Signal Distribution Analysis (PhoSDA)", Physical Chemistry Chemical Physics (PCCP), M. Selmke, R. Schachoff, M. Braun, F. Cichos, 2013 (advance article)
  17. "Twin-Focus Photothermal Correlation Spectroscopy", RSC Advances (RSC Adv.), Vol. 3, pp. 394-400, M. Selmke, R. Schachoff, M. Braun, F. Cichos, 2013
  18. "Gaussian Beam Photothermal Single Particle Microscopy" (oa), Journal of the Optical Society of America A (JOSA A), Vol. 29, No.10, M. Selmke, M. Braun, F. Cichos, 2012
  19. "Photothermal Single Particle Microscopy: Detection of a Nanolens",  ACS Nano, Vol. 6, No. 3, pp. 2741–2749, M. Selmke, M. Braun, F. Cichos, 2012
  20. "Nano-lens Diffraction around a Single Heated Nano Particle" (oa), Optics Express (Opt. Express), Vol. 20, No. 7, pp. 8055-8070, M. Selmke, M. Braun, F. Cichos, 2012, same article republished in the Virtual Journal for Biomedical Optics, Vol. 7, Iss. 52012
  21. "Measuring Flow Profiles and Slip by Single Molecule Tracking Experiments in Thin Liquid Films", The Journal of Physical Chemistry C (J. Phys. Chem. C), Vol. 114 (10), pp 4479-4485, A. Schob, M. Pumpa, M. Selmke and F. Cichos, 2010
  22. "Temperature dependent Single Molecule Rotational Dynamics in PMA", Physical Chemistry Chemical Physics (PCCP), Vol. 13, 1849-1856, S. Adhikari, M. Selmke and F. Cichos, 2011
  23. "Theory of Hot Brownian Motion", Soft Matter, Vol. 7, 3441-3452, D. Rings, M. Selmke, F. Cichos and K. Kroy2011
  24. "Hot Brownian Motion", Physical Review Letters (Phys. Rev. Lett.), 105, 090604, D. Rings, R. Schachoff, M. Selmke, F. Cichos, K. Kroy, 2010

other published arcticles

  1. "Revisiting the round-bottom flask experiment", arXiv:1612:09563, M. Selmke and  S. Selmke2016
  2. "Artificial Circumzenithal and Circumhorizontal Arcs", arXiv:1608:08664, M. Selmke and S. Selmke2016
  3. "The physics of the photothermal detection of single absorbing nano-objects: a review" (oa), arXiv:1510:08669, M. Selmke and F. Cichos2015.
  4. "Intensity distribution of the parhelic circle and embedded parhelia at low solar elevations: theory and experiments" (oa), arXiv:1412.8033, S. Borchardt and M. Selmke, 2014
  5. "Energy Redistribution Signitarures in Tranmission microscopy of Rayleigh- and Mie- particles" (oa), arXiv:1404.0567v1M. Selmke and F. Cichos, 2014
  6. "Hot Brownian Motion" (oa), arXiv:1003.4596v2D. Rings, R. Schachoff, M. Selmke, F. Cichos, K. Kroy, 2010
  7. "Photonic Rutherford scattering: A Classical and Quantum Mechanical Analogy in Ray- and Wave-Optics" (oa), arXiv:1208.5593, M. Selmke, F. Cichos, 2013
  8. "Photothermal single particle Microscopy" (oa), arXiv:1105.3815v1, M. Selmke, M. Braun, F. Cichos, 2011
  9. "Nanolens diffraction around a single heated nano particle" (oa), arXiv:1109.2772v1, M. Selmke, M. Braun, F. Cichos, 2011