arXiv subjects

Marc Thilo Figge

Publications and source records attributed to Marc Thilo Figge.

6 recordsLinked to original sources

arXiv2022

Guided-deconvolution for Correlative Light and Electron Microscopy

Correlative light and electron microscopy is a powerful tool to study the internal structure of cells. It combines the mutual benefit of correlating light (LM) and electron (EM) microscopy information. However, the classical approach of overlaying LM onto EM images to assign functional to structural information is hampered by the large discrepancy in structural detail visible in the LM images. This paper aims at investigating an optimized approach which we call EM-guided deconvolution. It attempts to automatically assign fluorescence-labelled structures to details visible in the EM image to bridge the gaps in both resolution and specificity between the two imaging modes.

cs.CV↗

arXiv1999

Peierls transition with acoustic phonons and twist deformation in carbon nanotubes

We consider the Peierls instability due to the interaction of electrons with both acoustic and optical phonons. We suggest that such a transition takes place in carbon nanotubes with small radius. The topological excitations and the temperature dependence of the conductivity resulting from the electron-lattice interactions are considered.

cond-mat.soft↗

arXiv1999

Magnetic Susceptibility Due to Disorder-Induced Neutral Solitons in Interacting Polymer Chains

We study the magnetic response due to neutral solitons induced by disorder in polymer materials. We account for interchain interactions, which, if sufficiently strong, result in a bond-ordered phase, in which the neutral solitons are bound into pairs. We analytically calculate the corresponding pair size distribution. As the spins of the solitons have a distance dependent antiferromagnetic coupling, this allows us to calculate the magnetic susceptibility in the ordered phase. At low temperatures, the result deviates from the usual Curie behavior in a way that depends on the relative strength of the disorder and the interchain interactions. We compare our results to the observed magnetic susceptibility of trans-polyacetylene and we suggest new experiments extending towards lower temperatures.

cond-mat.soft↗

arXiv1998

Disorder-induced neutral solitons in degenerate ground state polymers

In this letter, we study the effects of weak off-diagonal disorder on conjugated polymers with a doubly degenerate ground-state. We find that disorder induces a finite density of neutral solitons in the lattice dimerization of a polymer chain. Interchain interactions result in a linear potential between the solitons and, if sufficiently strong, bind them into pairs resulting in an exponential suppression of the soliton density. As neutral solitons carry spin 1/2, they contribute to the polymer's magnetic properties. We calculate the magnetic susceptibility and suggest measurements of the magnetic susceptibility in {\it trans}-polyacetylene at low temperatures.

cond-mat.soft↗

arXiv1998

Critical temperature and density of spin-flips in the anisotropic random field Ising model

We present analytical results for the strongly anisotropic random field Ising model, consisting of weakly interacting spin chains. We combine the mean-field treatment of interchain interactions with an analytical calculation of the average chain free energy (``chain mean-field'' approach). The free energy is found using a mapping on a Brownian motion model. We calculate the order parameter and give expressions for the critical random magnetic field strength below which the ground state exhibits long range order and for the critical temperature as a function of the random magnetic field strength. In the limit of vanishing interchain interactions, we obtain corrections to the zero-temperature estimate by Imry and Ma [Phys. Rev. Lett. 35, 1399 (1975)] of the ground state density of domain walls (spin-flips) in the one-dimensional random field Ising model. One of the problems to which our model has direct relevance is the lattice dimerization in disordered quasi-one-dimensional Peierls materials, such as the conjugated polymer trans-polyacetylene.

cond-mat.stat-mech↗

arXiv1997

Disorder-induced solitons in conjugated polymers

We show that weak off-diagonal disorder in degenerate ground state conjugated polymers results in a finite density of randomly positioned kinks (solitons and antisolitons) in the lattice dimerization. For realistic values of the disorder, these kinks should clearly show up in the optical and magnetic properties.

cond-mat↗