We have offered a method of obtaining fine-structured vibronic spectra of fullerenes. At liquid-h... more We have offered a method of obtaining fine-structured vibronic spectra of fullerenes. At liquid-helium temperatures tens of narrow lines with half-width ≈ 0.5 me V have been observed in the emission and absorption spectra of fullerene molecules embedded in the matrices of some organic crystals. Using this method, the Zeeman effect on the C70 molecules has been observed for the
We demonstrate a topology-optimized coupler for a ring-shaped photonic crystal waveguide to impro... more We demonstrate a topology-optimized coupler for a ring-shaped photonic crystal waveguide to improve the coupling of light located in the slow-light regime. An enhancement of the coupling efficiency of up to 2.5 dB is experimentally demonstrated.
Optical coherent control experiments in semiconductors reveal how inhomogeneous broadening must b... more Optical coherent control experiments in semiconductors reveal how inhomogeneous broadening must be taken into account in contrast to previous coherent control experiments in atomic and molecular systems. With spectral resolution of the coherent control signal, the optical phases involved in the interplay between the homogeneous and inhomogeneous broadenings are measured. Based on these experiments, a coherent control model describing the
Physical review. B, Condensed matter, Jan 15, 1993
... 74, 1279 (1990) [INSPEC][CAS]. D. Oberhauser, K.-H. Pantke, JM Hvam, K.-H. Schlaad, G. Weiman... more ... 74, 1279 (1990) [INSPEC][CAS]. D. Oberhauser, K.-H. Pantke, JM Hvam, K.-H. Schlaad, G. Weimann, and C. Klingshirn, Proceedings of the International Conference on Laser '91, San Diego, 1991 (STS, San Diego, 1992), p. 368. ... S. Bar-Ad and I. Bar-Joseph, Phys. Rev. Lett. ...
Journal of Experimental and Theoretical Physics Letters, 1998
The effect of photoexcited free carriers on the absorption spectra dynamics of GaAs/AlxGa1−x As s... more The effect of photoexcited free carriers on the absorption spectra dynamics of GaAs/AlxGa1−x As superlattices is investigated experimentally by the pump-probe method. A sharp change in the shift of the excitonic resonance energy from the low-to the high-energy direction is found to occur at the moment that the electromagnetic radiation of the pump and probe beams overlap in the case of band-band excitation. This phenomenon is explained in a model of scattering of high-energy electron-hole pairs. The dephasing time of free high-energy particles is experimentally estimated to be several tens of femtoseconds.
We demonstrate a new ultrafast pump-probe technique using terahertz pulses to investigate carrier... more We demonstrate a new ultrafast pump-probe technique using terahertz pulses to investigate carrier transport and screening in semiconductors. As an example we have studied the temporal evolution of the local electric field in a dipole antenna, used for generation of ultrafast terahertz pulses. Ultrafast screening effects are shown to be important for both carrier transport and the emission of THz
We investigate waveguiding of long-range surface plasmon polaritons in periodic arrays of scatter... more We investigate waveguiding of long-range surface plasmon polaritons in periodic arrays of scatterers at telecommunication wavelengths. A propagation loss of approximately 6 dB/mm and a coupling loss of 0.5 dB is reported for 8-mum-wide channels
... quantization quantum confinement and uniaxial strain. These three bands have different polari... more ... quantization quantum confinement and uniaxial strain. These three bands have different polarization properties, with the consequence that the lowest confined state is, in general, polarized along the direction of weakest confinement. This explains the polarization anisotropy ...
... In a recent work of Castella and Wilkins,15 however, the problem is studied for a wider range... more ... In a recent work of Castella and Wilkins,15 however, the problem is studied for a wider range of correlation lengths. ... Rev. B 55, 5253 (1997). 15 H. Castella and JW Wilkins, Phys. Rev. B 58, 16 186 (1998). 16 A. Melliti, MA Maaref, and R. Planel, J. Lumin. 78, 25 (1998). ...
... B 54, 4436 (1996). 28 KI Kang, AD Kepner, SV Gaponenko, SW Koch, YZ Hu, and N. Peyghambarian,... more ... B 54, 4436 (1996). 28 KI Kang, AD Kepner, SV Gaponenko, SW Koch, YZ Hu, and N. Peyghambarian, Phys. Rev. B 48, 15 449 (1993). 29 U. Woggon, O. Wind, W. Langbein, O. Gogolin, and C. Kling-shirn, J. Lumin. 59, 135 (1994). 30 W. Langbein and JM Hvam, Phys. Rev. ...
We have offered a method of obtaining fine-structured vibronic spectra of fullerenes. At liquid-h... more We have offered a method of obtaining fine-structured vibronic spectra of fullerenes. At liquid-helium temperatures tens of narrow lines with half-width ≈ 0.5 me V have been observed in the emission and absorption spectra of fullerene molecules embedded in the matrices of some organic crystals. Using this method, the Zeeman effect on the C70 molecules has been observed for the
We demonstrate a topology-optimized coupler for a ring-shaped photonic crystal waveguide to impro... more We demonstrate a topology-optimized coupler for a ring-shaped photonic crystal waveguide to improve the coupling of light located in the slow-light regime. An enhancement of the coupling efficiency of up to 2.5 dB is experimentally demonstrated.
Optical coherent control experiments in semiconductors reveal how inhomogeneous broadening must b... more Optical coherent control experiments in semiconductors reveal how inhomogeneous broadening must be taken into account in contrast to previous coherent control experiments in atomic and molecular systems. With spectral resolution of the coherent control signal, the optical phases involved in the interplay between the homogeneous and inhomogeneous broadenings are measured. Based on these experiments, a coherent control model describing the
Physical review. B, Condensed matter, Jan 15, 1993
... 74, 1279 (1990) [INSPEC][CAS]. D. Oberhauser, K.-H. Pantke, JM Hvam, K.-H. Schlaad, G. Weiman... more ... 74, 1279 (1990) [INSPEC][CAS]. D. Oberhauser, K.-H. Pantke, JM Hvam, K.-H. Schlaad, G. Weimann, and C. Klingshirn, Proceedings of the International Conference on Laser '91, San Diego, 1991 (STS, San Diego, 1992), p. 368. ... S. Bar-Ad and I. Bar-Joseph, Phys. Rev. Lett. ...
Journal of Experimental and Theoretical Physics Letters, 1998
The effect of photoexcited free carriers on the absorption spectra dynamics of GaAs/AlxGa1−x As s... more The effect of photoexcited free carriers on the absorption spectra dynamics of GaAs/AlxGa1−x As superlattices is investigated experimentally by the pump-probe method. A sharp change in the shift of the excitonic resonance energy from the low-to the high-energy direction is found to occur at the moment that the electromagnetic radiation of the pump and probe beams overlap in the case of band-band excitation. This phenomenon is explained in a model of scattering of high-energy electron-hole pairs. The dephasing time of free high-energy particles is experimentally estimated to be several tens of femtoseconds.
We demonstrate a new ultrafast pump-probe technique using terahertz pulses to investigate carrier... more We demonstrate a new ultrafast pump-probe technique using terahertz pulses to investigate carrier transport and screening in semiconductors. As an example we have studied the temporal evolution of the local electric field in a dipole antenna, used for generation of ultrafast terahertz pulses. Ultrafast screening effects are shown to be important for both carrier transport and the emission of THz
We investigate waveguiding of long-range surface plasmon polaritons in periodic arrays of scatter... more We investigate waveguiding of long-range surface plasmon polaritons in periodic arrays of scatterers at telecommunication wavelengths. A propagation loss of approximately 6 dB/mm and a coupling loss of 0.5 dB is reported for 8-mum-wide channels
... quantization quantum confinement and uniaxial strain. These three bands have different polari... more ... quantization quantum confinement and uniaxial strain. These three bands have different polarization properties, with the consequence that the lowest confined state is, in general, polarized along the direction of weakest confinement. This explains the polarization anisotropy ...
... In a recent work of Castella and Wilkins,15 however, the problem is studied for a wider range... more ... In a recent work of Castella and Wilkins,15 however, the problem is studied for a wider range of correlation lengths. ... Rev. B 55, 5253 (1997). 15 H. Castella and JW Wilkins, Phys. Rev. B 58, 16 186 (1998). 16 A. Melliti, MA Maaref, and R. Planel, J. Lumin. 78, 25 (1998). ...
... B 54, 4436 (1996). 28 KI Kang, AD Kepner, SV Gaponenko, SW Koch, YZ Hu, and N. Peyghambarian,... more ... B 54, 4436 (1996). 28 KI Kang, AD Kepner, SV Gaponenko, SW Koch, YZ Hu, and N. Peyghambarian, Phys. Rev. B 48, 15 449 (1993). 29 U. Woggon, O. Wind, W. Langbein, O. Gogolin, and C. Kling-shirn, J. Lumin. 59, 135 (1994). 30 W. Langbein and JM Hvam, Phys. Rev. ...
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