Search

Your search keyword '"Schwefel, Harald G. L."' showing total 18 results
Start Over Author "Schwefel, Harald G. L." Publisher ieee
18 results on '"Schwefel, Harald G. L."'

1. Tunable Dual Comb Source in a Kerr Microresonator

Author

Qureshi, Pierce C., primary, Ng, Vincent, additional, Azeem, Farhan, additional, Trainor, Luke S., additional, Schwefel, Harald G. L., additional, Coen, Stéphane, additional, Erkintalo, Miro, additional, and Murdoch, Stuart G., additional

Published
2023
Full Text
View/download PDF

8. Analytical study of free-space coupling of THz radiation for a new radioastronomy receiver concept

Author

Botello, Gabriel Santamaría, Abdalmalak, Kerlos Atia, Schlecht, Maria-Theresa, González-Ovejero, David, Sedlmeir, Florian, Schwefel, Harald G. L., Malzer, Stefan, Weber, Heiko, Segovia-Vargas, Daniel, McCarthy, Darragh, Murphy, John Anthony, Döhler, Gottfried H., García Muñoz, Luis-Enrique, Botello, Gabriel Santamaría, Abdalmalak, Kerlos Atia, Schlecht, Maria-Theresa, González-Ovejero, David, Sedlmeir, Florian, Schwefel, Harald G. L., Malzer, Stefan, Weber, Heiko, Segovia-Vargas, Daniel, McCarthy, Darragh, Murphy, John Anthony, Döhler, Gottfried H., and García Muñoz, Luis-Enrique

Abstract

In this paper, a scheme for coupling free-space THz radiation into a nonlinear whispering-gallery mode (WGM) resonator is presented. The purpose is to detect the weak THz radiation from the cosmic microwave background (CMB) by up-converting the signal into the optical domain via the nonlinearity of the medium. Such high-sensitivity receiver has theoretically shown capabilities towards photon counting at room temperature, however, it is critical to efficiently couple the THz radiation into the resonator. Therefore, by using the Schelkunoff-Waterman method (the so called T-matrix method) we perform an analytical evaluation of two different free-space coupling techniques: a freespace Gaussian beam, and a Gaussian beam incident in a silicon lens under total internal reflection. By comparing the excited modes in the resonator, the optimal parameters for each case are given.

Published
2017

9. Study of free-space coupling into mm-wave whispering-gallery mode resonators for a radioastronomy receiver

Author

Santamaría-Botello, Gabriel, Abdalmalak, Kerlos Atia, Schlecht, Maria-Theresa, González-Ovejero, David, Sedlmeir, Florian, Schwefel, Harald G. L., Malzer, Stefan, Weber, Heiko, Segovia-Vargas, Daniel, McCarthy, Darragh, Murphy, John Anthony, Döhler, Gottfried H., García Muñoz, Luis Enrique, Santamaría-Botello, Gabriel, Abdalmalak, Kerlos Atia, Schlecht, Maria-Theresa, González-Ovejero, David, Sedlmeir, Florian, Schwefel, Harald G. L., Malzer, Stefan, Weber, Heiko, Segovia-Vargas, Daniel, McCarthy, Darragh, Murphy, John Anthony, Döhler, Gottfried H., and García Muñoz, Luis Enrique

Abstract

In this paper, the coupling mechanism of a free-space Gaussian beam into a whispering-gallery mode resonator through a dielectric lens is mathematically modeled and numerically solved by means of the Schelkunoff-Waterman method (the so called T-matrix method). This approach allows in principle, to quickly analyze the performance of different near-field coupling mechanisms with arbitrary excitations. The aim is to efficiently excite a WGM into a nonlinear dielectric resonator in order to detect the weak mm-wave radiation from the cosmic microwave background (CMB) by up-converting the signal into the optical domain via the nonlinearity of the medium.

Published
2017

10. Study of free-space coupling into mm-wave whispering-gallery mode resonators for a radioastronomy receiver

Author

Santamaria-Botello, Gabriel, primary, Abdalmalak, Kerlos Atia, additional, Schlecht, Maria-Theresa, additional, Gonzalez-Ovejero, David, additional, Sedlmeir, Florian, additional, Schwefel, Harald G. L., additional, Malzer, Stefan, additional, Weber, Heiko, additional, Segovia-Vargas, Daniel, additional, McCarthy, Darragh, additional, Murphy, John Anthony, additional, Dohler, Gottfried H., additional, and Garcia Munoz, Luis Enrique, additional

Published
2017
Full Text
View/download PDF

11. Analytical study of free-space coupling of THz radiation for a new radioastronomy receiver concept

Author

Botello, Gabriel Santamaria, primary, Abdalmalak, Kerlos Atia, additional, Schlecht, Maria-Theresa, additional, Gonzalez-Ovejero, David, additional, Sedlmeir, Florian, additional, Schwefel, Harald G. L., additional, Malzer, Stefan, additional, Weber, Heiko, additional, Segovia-Vargas, Daniel, additional, McCarthy, Darragh, additional, Murphy, John Anthony, additional, Dohler, Gottfried H., additional, and Munoz, Luis-Enrique Garcia, additional

Published
2017
Full Text
View/download PDF

14. Dielectric Rod Waveguide Antenna as THz Emitter for Photomixing Devices.

Author

Rivera-Lavado, Alejandro, Preu, Sascha, Garcia-Munoz, Luis Enrique, Generalov, Andrey, Montero-de-Paz, Javier, Dohler, Gottfried, Lioubtchenko, Dmitri, Mendez-Aller, Mario, Sedlmeir, Florian, Schneidereit, Martin, Schwefel, Harald G. L., Malzer, Stefan, Segovia-Vargas, Daniel, and Raisanen, Antti V.

Subjects
WAVEGUIDE antennas, DIELECTRIC waveguides, WHISPERING gallery modes, RESONATORS, SEMICONDUCTORS
Abstract

We propose a dielectric rod waveguide antenna (DRW) integrated with a photomixer as a THz emitter. This represents a different approach as opposed to the classical solution of a substrate lens. Main goals are an inexpensive alternative to substrate lenses, reduction of both reflections on the semiconductor-air interface and scattering of terahertz-generated power into the substrate. A radiation pattern measured at 137 GHz is shown as a proof-of-concept. In order to increase radiated power, the improvement of the rod antenna is discussed. Finally, as an application example, evanescent coupling of the DRW into a high index whispering gallery mode resonator is shown. [ABSTRACT FROM PUBLISHER]

Published
2015
Full Text
View/download PDF

17. Mode-hop-free tunable optical parametric oscillator utilizing a whispering gallery mode resonator.

Author

Fortsch, Michael, Schunk, Gerhard, Sedlmeir, Florian, Fuurst, Josef, Wittmann, Christoffer, Strekalov, Dmitry, Schwefel, Harald G. L., Marquardt, Christoph, and Leuchs, Gerd

Abstract

We report on a compact and stable optical parametric oscillator in a whispering gallery mode resonator, that combines very low pump thresholds with versatile tunability. [ABSTRACT FROM PUBLISHER]

Published
2012

Catalog

Books, media, physical & digital resources
See catalog results