DFG CRC M3 | Institut für Optische und Elektronische Materialien

DFG Collaborative Research Centre M³

In 2012 the DFG (German Research Foundation) established the collaborative research centre:

“Tailor-Made Multi-Scale Material Systems – M³”

“Maßgeschneiderte Multiskalige Materialsysteme -M³”

This is a collaborative effort of Hamburg University of Technology as the leading institution, the University of Hamburg and the Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research.

The goal of the collaborative research centre (CRC) is the development of modelling and experimental methods to describe, manufacture and characterize materials structured on multiple scales leading to tailor-made mechanical, electrical and photonic properties. The advancement and integration of atomic, mesoscale and continuum material models should establish an understanding of the effects of the hierarchical structure on the material behaviour. The multiscale structure is achieved by a specific arrangement of individual elements at different discrete length scales. The building blocks are made of polymeric, ceramic or metallic materials or their structured or functionalized composites. The optimization of a specific class of materials is not the primary task. Instead, the focus of the planned CRC lies in the development of scientific concepts. By choosing materials and geometries on each hierarchy level the CRC intends to realize novel material property profiles.

The CRC has three research areas where research area C is dedicated to photonics and is coordinated by Institute of Optical and Electronic Materials

Project area C “Material systems for high temperature photonics”

Two institutes of the Hamburg University of Technology (TUHH) and two institutes of the University of Hamburg (U Hamburg) jointly applied for this research area and now cooperate closely within its scope.

Participants of the Research Area C:

Institute of “Optical and Electronic Materials” (TUHH),
Institute of “Advanced Ceramics” (TUHH),
Institute of “Applied Physics” (U Hamburg) and
Institute of “Physical Chemistry” (U Hamburg).

The Institute of Optical and Electronic Materials focuses on the projects

Structured emitters and filters for enhanced optical coupling in thermophotovoltaics (C1)
Multiscaled ceramic based photonic structures for strong reflection of thermal radiation in high temperature environments (C2).

In project area C novel hierarchical nanostructured material systems are studied on the basis of thermally stable ceramics and metals for photonics at high temperatures with application perspectives for thermophotovoltaic systems (TPV) and thermal barrier coatings (TBC). The goal of the project area is to control thermal radiation in structured materials. One direction of research deals with suppression of thermal radiation propagation in transparent materials due to strong reflection and scattering, and the other investigates enhancement of thermal transfer due to radiation by manipulation of the optical density of states. In particular, dielectric and metallodielectric 3D photonic crystal structures (PhC) and hyperbolic metamaterials are at the focus of the investigation.

C1 “Structured emitters and filters for enhanced optical coupling in thermophotovoltaics”

Strong optical coupling between the emitter and the photovoltaic cell has the potential of significantly enhancing the electrical power extraction from thermophotovoltaic systems (TPV) generated by thermal radiation. The efficiency can also be increased by adjusting the emission spectrum to the band gap of the photovoltaic cell. The project aims at the development of novel 1D, 2D und 3D periodical and aperiodical ceramic, metallic and carbon nanotube (CNT) based metamaterials which would allow systematic control of optical coupling and spectral emission properties and at the same time suppress thermal conductivity.

Literature:

Tumkur, T.; Zhu, G.; Black, P.; Barnakov, Yu A.; Bonner, C. E. and Noginov, M. A.; Control of spontaneous emission in a volume of functionalized hyperbolic metamaterial, Appl. Phys. Lett 99, 151115, (2011);

Narimanov, E. E. and Smolyaninov, I. I.; Beyond Stefan-Boltzmann Law: Thermal Hyper-Conductivity, Arxiv preprint, arXiv:1109.5444, (2011);

Poddubny, A. N.; Belov, P. A. and Kivshar, Y. S.; Spontaneous radiation of a finite-size dipole emitter in hyperbolic media, Phys. Rev. A 84, 23807, (2011).

C2 “Multiscaled ceramic based photonic structures for strong reflection of thermal radiation in high temperature environments”

The goal of the project is to realise novel 3D structured periodical and aperiodical oxide ceramic based material systems which strongly reflect or scatter thermal radiation and which remain stable at high temperatures. The structural parameters should be adjusted for effective and broadband reflection and negligible absorption of thermal radiation at infrared wavelengths and hemispherical incidence. Taking into account that the heat transfer at high temperatures is significantly influenced by the thermal radiation, a strongly reflective coating can thus be used as a novel thermal barrier coating (TBC) which reduces the thermal load on components such as gas turbine blades by limiting the heat transfer.