Scientific Commons: B. Dietz

Friedel Oscillations in Microwave Billiards (2009)

Baecker, A., Dietz, B., Friedrich, T., Miski-Oglu, M., Richter, A., Schaefer, F., ...

Friedel oscillations of electron densities near impurities have an analog in microwave billiards, which we measure for pseudo-integrable and mixed dynamics geometries. It is expected and found that...

Nonperiodic echoes from quantum mushroom billiard hats (2009)

Dietz, B., Friedrich, T., Miski-Oglu, M., Richter, A., Schäfer, F., Seligmann, T. H.

Nonperiodic tunable quantum echoes have been observed in experiments with an open microwave billiard whose geometry under certain conditions provides Fibonacci like sequences of classical delay...

Experimental Test of a Two-dimensional Approximation for Dielectric Microcavities (2009)

Bittner, S., Dietz, B., Miski-Oglu, M., Iriarte, P. Oria, Richter, A., Schäfer, F.

Open dielectric resonators of different shapes are widely used for the manufacture of microlasers. A precise determination of their resonance frequencies and widths is crucial for their design. Most...

Induced Violation of Time-Reversal Invariance in the Regime of Weakly Overlapping Resonances (2009)

Dietz, B., Friedrich, T., Harney, H. L., Miski-Oglu, M., Richer, A., Schaefer, F., ...

We measure the complex scattering amplitudes of a flat microwave cavity (a "chaotic billiard"). Time-reversal T-invariance is partially broken by a magnetized ferrite placed within the cavity. We...

Economic modeling of the combined effects of HIV disease, heart disease and lipoatrophy based on ACTG 5142 trial data (2008)

Simpson, KN, Rajagopalan, R, Dietz, B, Garren, K, Riddler, S, Haubrich, R

No abstract available.

Cost-effectiveness and budget impact of lopinavir/ritonavir and atazanavir plus ritonavir regimens based on 48-week results from the CASTLE study (2008)

Simpson, KN, Rajagopalan, R, Dietz, B

No abstract available.

Cost-effectiveness of switching to second-line therapy with lopinavir/ritonavir in Africa: estimates based on DART trial results and costs for Uganda (2008)

Simpson, KN, Dietz, B, Rahim, SX, Rajagopalan, R

No abstract available.

Chaotic Scattering in the Regime of Weakly Overlapping Resonances (2008)

Dietz, B., Friedrich, T., Harney, H. L., Miski-Oglu, M., Richter, A., Schaefer, F., ...

We measure the transmission and reflection amplitudes of microwaves in a resonator coupled to two antennas at room temperature in the regime of weakly overlapping resonances and in a frequency range...

Bouncing ball orbits and symmetry breaking effects in a three-dimensional chaotic billiard (2008)

Dietz, B., Moessner, B., Papenbrock, T., Reif, U., Richter, A.

We study the classical and quantum mechanics of a three-dimensional stadium billiard. It consists of two quarter cylinders that are rotated with respect to each other by 90 degrees, and it is...

Spectral fluctuations of billiards with mixed dynamics: from time series to superstatistics (2008)

Abul-Magd, A. Y., Dietz, B., Friedrich, T., Richter, A.

A statistical analysis of the eigenfrequencies of two sets of superconducting microwave billiards, one with mushroom-like shape and the other from the familiy of the Limacon billiards, is presented....

When intelligence is (dys)functional for achieving sales performance (2008)

Verbeke, W.J., Belschak, F.D., Bakker, A.B., Dietz, B.

Using two samples of salespeople, the authors investigate how a combination of general mental ability (GMA) and specific skills and capabilities (social competence and thinking styles) enables...

Personal and economic burden of late-stage rheumatoid arthritis among patients treated with adalimumab: an evaluation from a patient's perspective (2008)

Mittendorf, T., Dietz, B., Sterz, R., Cifaldi, M. A., Kupper, H., Von Der Schulenburg, J.-M.

Objectives. This study evaluated the patients’ perspective of burden of disease among 505 patients with severe, long-standing rheumatoid arthritis receiving adalimumab. Methods. Health-related...

Spectral properties of Bunimovich mushroom billiards (2007)

Dietz, B., Friedrich, T., Miski-Oglu, M., Richter, A., Schaefer, F.

Properties of a quantum mushroom billiard in the form of a superconducting microwave resonator have been investigated. They reveal unexpected nonuniversal features such as, e.g., a supershell effect...

Induced Time-Reversal Symmetry Breaking Observed in Microwave Billiards (2007)

Dietz, B., Friedrich, T., Harney, H. L., Miski-Oglu, M., Richter, A., Schaefer, F., ...

Using reciprocity, we investigate the breaking of time-reversal (T) symmetry due to a ferrite embedded in a flat microwave billiard. Transmission spectra of isolated single resonances are not...

First Experimental Observation of Superscars in a Pseudointegrable Barrier Billiard (2007)

Bogomolny, E., Dietz, B., Friedrich, T., Miski-Oglu, M., Richter, A., Schaefer, F., ...

With a perturbation body technique intensity distributions of the electric field strength in a flat microwave billiard with a barrier inside up to mode numbers as large as about 700 were measured. A...

Induced time-reversal symmetry breaking observed in microwave billiards (2007)

Dietz, B., Friedrich, T., Harney, H. L., Miski-Oglu, M., Richter, A., Schafer, F., ...

Rabi Oscillations at Exceptional Points in Microwave Billiards (2006)

Dietz, B., Friedrich, T., Metz, J., Miski-Oglu, M., Richter, A., Sch{ä}fer, F., ...

We experimentally investigated the decay behavior with time t of resonances near and at exceptional points, where two complex eigenvalues and also the associated eigenfunctions coalesce. The...

First Experimental Observation of Superscars in a Pseudointegrable Barrier Billiard (2006)

Bogomolny, E., Dietz, B., Friedrich, T., Miski-Oglu, M., Richter, A., Schaefer, F., ...

With a perturbation body technique intensity distributions of the electric field strength in a flat microwave billiard with a barrier inside up to mode numbers as large as about 700 were measured. A...

Nonperiodic echoes from mushroom billiard hats (2006)

Dietz, B., Friedrich, T., Miski-Oglu, M., Richter, A., Seligman, T. H., Zapfe, K.

Mushroom billiards have the remarkable property to show one or more clear cut integrable islands in one or several chaotic seas, without any fractal boundaries. The islands correspond to orbits...

Spectral statistics in an open parametric billiard system (2006)

Dietz, B., Heine, A., Richter, A., Bohigas, O., Leboeuf, P.

We present experimental results on the eigenfrequency statistics of a superconducting, chaotic microwave billiard containing a rotatable obstacle. Deviations of the spectral fluctuations from...

Spectral statistics in an open parametric billiard system (2006)

Dietz, B., Heine, A., Richter, A., Bohigas, O., Leboeuf, P.

We present experimental results on the eigenfrequency statistics of a superconducting, chaotic microwave billiard containing a rotatable obstacle. Deviations of the spectral fluctuations from...

Spectral statistics in an open parametric billiard system (2006)

Dietz, B., Heine, A., Richter, A., Bohigas, O., Leboeuf, P.

We present experimental results on the eigenfrequency statistics of a superconducting, chaotic microwave billiard containing a rotatable obstacle. Deviations of the spectral fluctuations from...

Spectral statistics in an open parametric billiard system (2006)

Dietz, B., Heine, A., Richter, A., Bohigas, O., Leboeuf, P.

We present experimental results on the eigenfrequency statistics of a superconducting, chaotic microwave billiard containing a rotatable obstacle. Deviations of the spectral fluctuations from...

First experimental evidence for quantum echoes in scattering systems (2004)

Dembowski, C., Dietz, B., Friedrich, T., Heine, A., Mejia-Monasterio, C., ...

A self-pulsing effect termed quantum echoes has been observed in experiments with an open superconducting and a normal conducting microwave billiard whose geometry provides soft chaos, i.e. a mixed...

Encircling an Exceptional Point (2004)

Dembowski,C., Dietz,B., Gräf,H.D., Harney,H.L., Heine,A., Heiss,W.D., ...

We calculate analytically the geometric phases that the eigenvectors of a parametric dissipative two-state system described by a complex symmetric Hamiltonian pick up when an exceptional point (EP)...

Encircling an exceptional point (2004)

Dembowski,C., Dietz,B., Harney,H. L., Heine,A., Heiss,W. D., ...

We calculate analytically the geometric phases that the eigenvectors of a parametric dissipative two-state system described by a complex symmetric Hamiltonian pick up when an exceptional point (EP)...

Encircling an Exceptional Point (2004)

Dembowski, C., Dietz, B., Harney, H. L., Heine, A., Heiss, W. D., ...

We calculate analytically the geometric phases that the eigenvectors of a parametric dissipative two-state system described by a complex symmetric Hamiltonian pick up when an exceptional point (EP)...

Encircling an Exceptional Point (2004)

Dembowski, C., Dietz, B., Gräf, H.D., Harney, H.L., Heine, A., Heiss, W.D., ...

We calculate analytically the geometric phases that the eigenvectors of a parametric dissipative two-state system described by a complex symmetric Hamiltonian pick up when an exceptional point (EP)...

Encircling an exceptional point (2004)

Dembowski, C., Dietz, B., Harney, H. L., Heine, A., Heiss, W. D., ...

We calculate analytically the geometric phases that the eigenvectors of a parametric dissipative two-state system described by a complex symmetric Hamiltonian pick up when an exceptional point (EP)...

Comment on ''Exceptional points and double poles of the S matrix'' (2003)

Dembowski, C., Dietz, B., Harney, H. L., Heine, A., Heiss, W. D., ...

In a recent paper [Phys. Rev. E 67, 026204 (2003)], Rotter calculates the geometric phases that are picked up by the eigenvectors of a two-state quantum system when an exceptional point is encircled....

Observation of a chiral state in a microwave cavity (2003)

Dembowski,C., Dietz,B., Graf,H. D., Harney,H. L., Heine,A., Heiss,W. D., ...