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Papers by Bernd Huettner

Research paper thumbnail of Blauer Dunst und rote Fahnen? TabakarbeiterInnen im Bremen des 19. Jahrhunderts

Tabak und Gesellschaft, 2015

Research paper thumbnail of On the temperature dependence of the electronic thermal conductivity in metals when the electron and phonon subsystems are not in local equilibrium

Journal of Physics: Condensed Matter, 1998

ABSTRACT

Research paper thumbnail of IR-RTI oscillations during laser induced epitaxial GaN film growth and the role of free carrier concentration

Applied Surface Science, 2000

In this paper, we report on the growth of high quality GaN films by a laser assisted process, opt... more In this paper, we report on the growth of high quality GaN films by a laser assisted process, optimized for the growth of epitaxial nitrides. Growth mode and film thickness were controlled in situ by the measurement of infrared-radiation Ž. transmission intensity IR-RTI oscillations. In the case of a light absorbing film, these oscillations are damped. A model is presented to fit the experimental data and to determine the free carrier concentration during deposition. Comparison with Ž. room temperature RT values from Hall measurements showed a satisfying agreement.

Research paper thumbnail of On the theory of ps and sub-ps laser pulse interaction with metals I. Surface temperature

Applied Surface Science, 1996

A model is proposed describing the interaction of short laser pulses with metals. It is shown tha... more A model is proposed describing the interaction of short laser pulses with metals. It is shown that a generalized nonlocal heat flow in time leads to an equation of heat conduction with additional terms involving the time derivative of both the laser intensity and the coupling of the electrons to the phonons. The importance of the coefficient of heat exchange for the temperature distribution in metals and the different influence of its main parts, the electron phonon coupling and the averaged square phonon frequencies, is pointed out. For a laser pulse length of I ps the electron and phonon surface temperatures for Al, Cu. Nb and Pb are evaluated using a double temperature model with a nonlocal heat flow. This is compared with the results of a local heat flow approach and with the conventional theory.

Research paper thumbnail of On Brewster’s angle of metals

Journal of Applied Physics, 1995

ABSTRACT

Research paper thumbnail of Electrodynamics—Two Versions and One Problem

Journal of Modern Physics, 2014

Based on two versions of Maxwell's Equations we investigate the Poynting vector, the energy trans... more Based on two versions of Maxwell's Equations we investigate the Poynting vector, the energy transport and the dispersion relation both for right-and left-handed systems. Furthermore, it is shown that the latter systems are necessarily dispersive in contrast to the former ones. In the end we discuss a published example where the mixing of expressions of both versions of Maxwell's Equations leads to unphysical conclusions. The presentation demonstrates for students how flexible can be the work with different versions of electrodynamics but also how carefully one has to be thereby.

Research paper thumbnail of Femtosecond Laser Pulse Interactions with Metals

The Theory of Laser Materials Processing

ABSTRACT A new era of fundamental research and its application to surface processing has been cre... more ABSTRACT A new era of fundamental research and its application to surface processing has been created by the invention of femtosecond laser pulses. Theoretical aspects of these processes are considered in this chapter. The differences between these very short pulses and the more conventional longer pulses are discussed, including the electron-electron scattering time and the non-equilibrium electron distribution. The material properties of objects exposed to femtosecond laser pulses are discussed with particular reference to their optical and thermal properties. The problem of determining the electron and phonon temperature distributions is addressed by means of the two-temperature model and the extended two-temperature model.

Research paper thumbnail of Physics of transport at short laser pulses

Proceedings of SPIE, 2000

ABSTRACT

Research paper thumbnail of Method and device for detaching a segment of a material layer

Research paper thumbnail of Method and Device for Removing a Cut-Out from a Layer of Material

Research paper thumbnail of Beiträge zur Theorie der spezifischen Wärme und der thermischen Ausdehnung der amorphen Festkörper /

Research paper thumbnail of Optical properties of metals in the solid and liquid state: aluminium, indium, lead

Research paper thumbnail of Optical properties of polyvalent metals (Al, In, Pb)

Research paper thumbnail of Optical properties of polyvalent metals in the solid and liquid state: aluminum

Research paper thumbnail of On the short pulse laser heating of metals - a new approach

Research paper thumbnail of On the electronic thermal conductivity in metals when subsystems are not in equilibrium

Research paper thumbnail of An extended two-temperature model - a new approach for the laser metal interaction

Research paper thumbnail of Proceedings M4PL13

Research paper thumbnail of Thermodynamics and transport properties in the transient regime

Journal of Physics Condensed Matter

ABSTRACT

Research paper thumbnail of Physics of transport at short laser pulses

Proceedings of SPIE - The International Society for Optical Engineering

ABSTRACT

Research paper thumbnail of Blauer Dunst und rote Fahnen? TabakarbeiterInnen im Bremen des 19. Jahrhunderts

Tabak und Gesellschaft, 2015

Research paper thumbnail of On the temperature dependence of the electronic thermal conductivity in metals when the electron and phonon subsystems are not in local equilibrium

Journal of Physics: Condensed Matter, 1998

ABSTRACT

Research paper thumbnail of IR-RTI oscillations during laser induced epitaxial GaN film growth and the role of free carrier concentration

Applied Surface Science, 2000

In this paper, we report on the growth of high quality GaN films by a laser assisted process, opt... more In this paper, we report on the growth of high quality GaN films by a laser assisted process, optimized for the growth of epitaxial nitrides. Growth mode and film thickness were controlled in situ by the measurement of infrared-radiation Ž. transmission intensity IR-RTI oscillations. In the case of a light absorbing film, these oscillations are damped. A model is presented to fit the experimental data and to determine the free carrier concentration during deposition. Comparison with Ž. room temperature RT values from Hall measurements showed a satisfying agreement.

Research paper thumbnail of On the theory of ps and sub-ps laser pulse interaction with metals I. Surface temperature

Applied Surface Science, 1996

A model is proposed describing the interaction of short laser pulses with metals. It is shown tha... more A model is proposed describing the interaction of short laser pulses with metals. It is shown that a generalized nonlocal heat flow in time leads to an equation of heat conduction with additional terms involving the time derivative of both the laser intensity and the coupling of the electrons to the phonons. The importance of the coefficient of heat exchange for the temperature distribution in metals and the different influence of its main parts, the electron phonon coupling and the averaged square phonon frequencies, is pointed out. For a laser pulse length of I ps the electron and phonon surface temperatures for Al, Cu. Nb and Pb are evaluated using a double temperature model with a nonlocal heat flow. This is compared with the results of a local heat flow approach and with the conventional theory.

Research paper thumbnail of On Brewster’s angle of metals

Journal of Applied Physics, 1995

ABSTRACT

Research paper thumbnail of Electrodynamics—Two Versions and One Problem

Journal of Modern Physics, 2014

Based on two versions of Maxwell's Equations we investigate the Poynting vector, the energy trans... more Based on two versions of Maxwell's Equations we investigate the Poynting vector, the energy transport and the dispersion relation both for right-and left-handed systems. Furthermore, it is shown that the latter systems are necessarily dispersive in contrast to the former ones. In the end we discuss a published example where the mixing of expressions of both versions of Maxwell's Equations leads to unphysical conclusions. The presentation demonstrates for students how flexible can be the work with different versions of electrodynamics but also how carefully one has to be thereby.

Research paper thumbnail of Femtosecond Laser Pulse Interactions with Metals

The Theory of Laser Materials Processing

ABSTRACT A new era of fundamental research and its application to surface processing has been cre... more ABSTRACT A new era of fundamental research and its application to surface processing has been created by the invention of femtosecond laser pulses. Theoretical aspects of these processes are considered in this chapter. The differences between these very short pulses and the more conventional longer pulses are discussed, including the electron-electron scattering time and the non-equilibrium electron distribution. The material properties of objects exposed to femtosecond laser pulses are discussed with particular reference to their optical and thermal properties. The problem of determining the electron and phonon temperature distributions is addressed by means of the two-temperature model and the extended two-temperature model.

Research paper thumbnail of Physics of transport at short laser pulses

Proceedings of SPIE, 2000

ABSTRACT

Research paper thumbnail of Method and device for detaching a segment of a material layer

Research paper thumbnail of Method and Device for Removing a Cut-Out from a Layer of Material

Research paper thumbnail of Beiträge zur Theorie der spezifischen Wärme und der thermischen Ausdehnung der amorphen Festkörper /

Research paper thumbnail of Optical properties of metals in the solid and liquid state: aluminium, indium, lead

Research paper thumbnail of Optical properties of polyvalent metals (Al, In, Pb)

Research paper thumbnail of Optical properties of polyvalent metals in the solid and liquid state: aluminum

Research paper thumbnail of On the short pulse laser heating of metals - a new approach

Research paper thumbnail of On the electronic thermal conductivity in metals when subsystems are not in equilibrium

Research paper thumbnail of An extended two-temperature model - a new approach for the laser metal interaction

Research paper thumbnail of Proceedings M4PL13

Research paper thumbnail of Thermodynamics and transport properties in the transient regime

Journal of Physics Condensed Matter

ABSTRACT

Research paper thumbnail of Physics of transport at short laser pulses

Proceedings of SPIE - The International Society for Optical Engineering

ABSTRACT

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