Lattice Dynamics
Lattice Dynamics
Research Group Alexander Paarmann
Research Group Alexander Paarmann

Publications
2024
Giulia Carini, Richarda Niemann, Niclas Sven Mueller, Martin Wolf, Alexander Paarmann
Surface Phonon Polariton Ellipsometry
Dorothée S Mader, Richarda Niemann, Martin Wolf, Sebastian F Maehrlein, Alexander Paarmann
Sum-Frequency Generation Spectro-Microscopy in the Reststrahlen Band of Wurtzite-type Aluminum Nitride
Michael S Spencer, Joanna M Urban, Maximilian Frenzel, Niclas S Mueller, Olga Minakova, Martin Wolf, Alexander Paarmann, Sebastian F Maehrlein
Electro-Optic Cavities for In-Situ Measurement of Cavity Fields
Richarda Niemann, Niclas S Mueller, Sören Wasserroth, Guanyu Lu, Martin Wolf, Joshua D Caldwell, Alexander Paarmann
Spectroscopic and Interferometric Sum-Frequency Imaging of Strongly Coupled Phonon Polaritons in SiC Metasurfaces
J Álvarez-Cuervo, M Obst, S Dixit, G Carini, AIF Tresguerres-Mata, C Lanza, E Terán-García, G Álvarez-Pérez, L Fernández-Álvarez, K Diaz-Granados, R Kowalski, AS Senerath, NS Mueller, L Herrer, JM De Teresa, S Wasserroth, JM Klopf, T Beechem, M Wolf, LM Eng, TG Folland, A Tarazaga Martín-Luengo, J Martín-Sánchez, SC Kehr, AY Nikitin, JD Caldwell, P Alonso-González, A Paarmann
Unidirectional Ray Polaritons in Twisted Asymmetric Stacks
R. Kiessling, M. Wolf, and A. Paarmann
Spectral narrowing of a phonon resonance in time-domain sum-frequency spectroscopy
2023
Emanuele Galiffi, Giulia Carini, Xiang Ni, Gonzalo Álvarez-Pérez, Simon Yves, Enrico Maria Renzi, Ryan Nolen, Sören Wasserroth, Martin Wolf, Pablo Alonso-Gonzalez, Alexander Paarmann, Andrea Alù
Extreme light confinement and control in low-symmetry phonon-polaritonic crystals
Markus B Raschke, Mathias Schubert, Prineha Narang, Alexander Paarmann
Optical nanoprobe imaging and spectroscopy
Joseph Matson, Sören Wasserroth, Xiang Ni, Maximilian Obst, Katja Diaz-Granados, Giulia Carini, Enrico Maria Renzi, Emanuele Galiffi, Thomas G Folland, Lukas M Eng, J Michael Klopf, Stefan Mastel, Sean Armster, Vincent Gambin, Martin Wolf, Susanne C Kehr, Andrea Alù, Alexander Paarmann, Joshua D Caldwell
Controlling the propagation asymmetry of hyperbolic shear polaritons in beta-gallium oxide
Tuhin Khan, Ben John, Richarda Niemann, Alexander Paarmann, Martin Wolf, Martin Thämer
Compact oblique-incidence nonlinear widefield microscopy with paired-pixel balanced imaging
Riko Kiessling, Martin Wolf, Alexander Paarmann
Spectral narrowing of a phonon resonance in time-domain sum-frequency spectroscopy
Nikolai Christian Passler, Xiang Ni, Giulia Carini, Dmitry N Chigrin, Andrea Alù, Alexander Paarmann
Layer-resolved resonance intensity of evanescent polariton modes in anisotropic multilayers
Xiang Ni, Giulia Carini, Weiliang Ma, Enrico Maria Renzi, Emanuele Galiffi, Sören Wasserroth, Martin Wolf, Peining Li, Alexander Paarmann & Andrea Alù
Observation of directional leaky polaritons at anisotropic crystal interfaces
Guangwei Hu, Weiliang Ma, Debo Hu, Jing Wu, Chunqi Zheng, Kaipeng Liu, Xudong Zhang, Xiang Ni, Jianing Chen, Xinliang Zhang, Qing Dai, Joshua D. Caldwell, Alexander Paarmann, Andrea Alù , Peining Li  & Cheng-Wei Qiu
Real-space nanoimaging of hyperbolic shear polaritons in a monoclinic crystal
2022
Marcel Kohlmann, Christian Denker, Nikolai C Passler, Jana Kredl, Martin Wolf, Markus Münzenberg, Alexander Paarmann
Second harmonic generation from grating-coupled hybrid plasmon–phonon polaritons
Nikolai Christian Passler, Giulia Carini, Dmitry N. Chigrin, Alexander Paarmann
Layer-Resolved Resonance Intensity of Evanescent Polariton Modes in Anisotropic Multilayers
Yanhua Yue, Giacomo Melani, Harald Kirsch, Alexander Paarmann, Peter Saalfrank, R Kramer Campen, Yujin Tong
Structure and Reactivity of α-Al2O3(0001) Surfaces: How Do Al–I and Gibbsite-like Terminations Interconvert?
Richarda Niemann, Sören Wasserroth, Guanyu Lu, Sandy Gewinner, Marco De Pas, Wieland Schöllkopf, Joshua D. Caldwell, Martin Wolf, and Alexander Paarmann
Long-wave infrared super-resolution wide-field microscopy using sum-frequency generation
Mingze He, Thomas G. Folland, Jiahua Duan, Pablo Alonso-González, Simone De Liberato, Alexander Paarmann, and Joshua D. Caldwell
Anisotropy and Modal Hybridization in Infrared Nanophotonics Using Low-Symmetry Materials
Nikolai Passler, Xiang Ni, Guangwei Hu, Joseph Matson, Giulia Carini, Martin Wolf, Mathias Schubert, Andrea Alu, Joshua Caldwell, Thomas Folland, Alexander Paarmann
Hyperbolic shear polaritons in low-symmetry crystals
2021
Richarda Niemann, Sören Wasserroth, Guanyu Lu, Sandy Gewinner, Marco De Pas, Wieland Schöllkopf, Joshua D. Caldwell, Martin Wolf, and Alexander Paarmann
Infrared super-resolution wide-field microscopy using sum-frequency generation
Nikolai Passler, Xiang Ni, Guangwei Hu, Joseph Matson, Martin Wolf, Mathias Schubert, Andrea Alu, Joshua Caldwell, Thomas Folland, Alexander Paarmann
Hyperbolic Shear Polaritons in Low-Symmetry Crystals
Christopher J. Winta
Ph.D. Thesis, FU Berlin 2020. (open access)
2020
Nikolai C. Paßler
Ph.D. Thesis, FU Berlin 2020. (open access)
N.C. Passler, M. Jeannin, and A. Paarmann
Layer-Resolved Absorption of Light in Arbitrarily Anisotropic Heterostructures
Nikolai Christian Passler, Andreas Heßler, Matthias Wuttig, Thomas Taubner, Alexander Paarmann
Surface Polariton-Like s-Polarized Waveguide Modes in Switchable Dielectric Thin-Films on Polar Crystals
2019
N.C. Passler, A. Paarmann
Generalized 4 × 4 matrix formalism for light propagation in anisotropic stratified media: study of surface phonon polaritons in polar dielectric heterostructures: erratum
Riko Kiessling, Yujin Tong, Alexander J. Giles, Sandy Gewinner, Wieland Schoellkopf, Joshua D. Caldwell, Martin Wolf, Alexander Paarmann
Surface phonon polariton resonance imaging using long-wave infrared-visible sum-frequency generation microscopy
D. M. Juraschek, A. Paarmann; T. Kampfrath; S. F. Maehrlein
The THz sum-frequency counterparts of stimulated Raman scattering
Daniel C. Ratchford,* Christopher J. Winta,* Ioannis Chatzakis, Chase T. Ellis, Nikolai C. Passler, Jonathan Winterstein, Pratibha Dev, Ilya Razdolski, Joseph R. Matson, Joshua R Nolen, Joseph G. Tischler, Igor Vurgaftman, Michael B. Katz, Neeraj Nepal, Matthew T. Hardy, Jordan A. Hachtel, Juan Carlos Idrobo, Thomas L. Reinecke, Alexander J. Giles, D. Scott Katzer, Nabil D. Bassim, Rhonda M. Stroud, Martin Wolf, Alexander Paarmann, Joshua D. Caldwell
Controlling the Infrared Dielectric Function through Atomic-Scale Heterostructures
Nikolai Christian Passler, Ilya Razdolski, D. Scott Katzer, David F. Storm, Joshua D. Caldwell, Martin Wolf, Alexander Paarmann
Second Harmonic Generation from Phononic Epsilon-Near-Zero Berreman Modes in Ultrathin Polar Crystal Films
C.J. Winta, M. Wolf, and A. Paarmann
Low-temperature infrared dielectric function of hyperbolic α-quartz
2018
K. Pufahl, N.C. Passler, N.B. Grosse, M. Wolf, U. Woggon, and A. Paarmann
Controlling nanoscale air-gaps for critically coupled surface polaritons by means of non-invasive white-light interferometry
I. Razdolski, N.C. Passler, C.R. Gubbin, C.J. Winta, R. Cernansky, F. Martini, A. Politi, S.A. Maier, M. Wolf, A. Paarmann, and S. De Liberato
Second harmonic generation from strongly coupled localized and propagating phonon-polariton modes
N.C. Passler, I. Razdolski, S. Gewinner, W. Schöllkopf, S. De Liberato, C. Gubbin, J. Caldwell, M. Wolf, A. Paarmann
Nonlinear Response and Strong Coupling of Surface Phonon Polaritons
R. Kiessling, W.B. Colson, S. Gewinner, W. Schöllkopf, M. Wolf, A. Paarmann
Femtosecond single-shot timing and direct observation of subpulse formation in an infrared free-electron laser
M. Porer, M. Fechner, E.M. Bothschafter, L. Rettig, M. Savoini, V. Esposito, J. Rittmann, M. Kubli, M.J. Neugebauer, E. Abreu, T. Kubacka, T. Huber, G. Lantz, S. Parchenko, S. Grübel, A. Paarmann, J. Noack, P. Beaud, G. Ingold, U. Aschauer, S.L. Johnson, and U. Staub
Ultrafast Relaxation Dynamics of the Antiferrodistortive Phase in Ca Doped SrTiO3
S.F. Maehrlein, I. Radu, P. Maldonado, A. Paarmann, M. Gensch, A.M. Kalashnikova, R.V. Pisarev, M. Wolf, P.M. Oppeneer, J. Barker, and T. Kampfrath
Dissecting spin-phonon equilibration in ferrimagnetic insulators by ultrafast lattice excitation
N.C. Passler, C.R. Gubbin, T.G. Folland, I. Razdolski, D.S. Katzer, D.F. Storm, M. Wolf, S. De Liberato, J.D. Caldwell, and A. Paarmann
Strong Coupling of Epsilon-Near-Zero Phonon Polaritons in Polar Dielectric Heterostructures
C.J. Winta, S. Gewinner, W. Schöllkopf, M. Wolf, A. Paarmann
Second-harmonic phonon spectroscopy of α-quartz
R. Kiessling, S. Gewinner, A. Paarmann, W. Schöllkopf, M. Wolf
Synchronized Mid-Infrared Pulses at the Fritz Haber Institute IR-FEL
2017
N.C. Passler, A. Paarmann
Generalized 4 × 4 matrix formalism for light propagation in anisotropic stratified media: study of surface phonon polaritons in polar dielectric heterostructures
N.C. Passler, I. Razdolski, S. Gewinner, W. Schöllkopf, M. Wolf, and A. Paarmann
Second-Harmonic Generation from Critically Coupled Surface Phonon Polaritons
2016
A. Paarmann, I. Razdolski, S. Gewinner, W. Schöllkopf, and M. Wolf
Effects of crystal anisotropy on optical phonon resonances in midinfrared second harmonic response of SiC
I. Razdolski, Y. Chen, A.J. Giles, S. Gewinner, W. Schöllkopf, M. Hong, M. Wolf, V. Giannini, J.D. Caldwell, S.A. Maier, and A. Paarmann
Resonant Enhancement of Second-Harmonic Generation in the Mid-Infrared Using Localized Surface Phonon Polaritons in Subdiffractional Nanostructures
C.J. Winta, S. Gewinner, W. Schoellkopf, M. Wolf, and A. Paarmann
Second Harmonic Phonon Spectroscopy of α-Quartz
A. Paarmann, I. Razdolski, J. Caldwell, A. Giles, V. Giannini, S. Gewinner, W. Schoellkopf, S. Maier, and M. Wolf
Mid-Infrared Second Harmonic Spectroscopy Probing Surface Phonon Polariton Localization in SiC Nanopillars
2015
A. Paarmann, I. Razdolski, A. Melnikov, S. Gewinner, W. Schöllkopf, & M. Wolf
Second harmonic generation spectroscopy in the Reststrahl band of SiC using an infrared free-electron laser
W. Schöllkopf, S. Gewinner, H. Junkes, A. Paarmann, G. von Helden, H. Bluem, A.M.M. Todd
The new IR and THz FEL facility at the Fritz Haber Institute in Berlin
2014
M. Müller, A. Paarmann, and R. Ernstorfer
Femtosecond electrons probing currents and atomic structure in nanomaterials