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| 3. |
- Güttinger, J., et al.
(author)
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Energy-dependent path of dissipation in nanomechanical resonators
- 2017
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In: Nature Nanotechnology. - : Springer Science and Business Media LLC. - 1748-3387 .- 1748-3395. ; 12:7, s. 631-636
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Journal article (peer-reviewed)abstract
- Energy decay plays a central role in a wide range of phenomena, such as optical emission, nuclear fission, and dissipation in quantum systems. Energy decay is usually described as a system leaking energy irreversibly into an environmental bath. Here, we report on energy decay measurements in nanomechanical systems based on multilayer graphene that cannot be explained by the paradigm of a system directly coupled to a bath. As the energy of a vibrational mode freely decays, the rate of energy decay changes abruptly to a lower value. This finding can be explained by a model where the measured mode hybridizes with other modes of the resonator at high energy. Below a threshold energy, modes are decoupled, resulting in comparatively low decay rates and giant quality factors exceeding 1 million. Our work opens up new possibilities to manipulate vibrational states, engineer hybrid states with mechanical modes at completely different frequencies, and to study the collective motion of this highly tunable system.
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| 4. |
- Hildebrand, Angelica, et al.
(author)
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Elastic Neutron Scattering at 96 MeV
- 2004
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In: Proc. Int. Conf. on Nuclear Data for Science and Technology.
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Conference paper (other academic/artistic)
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| 5. |
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| 6. |
- Hildebrand, A, et al.
(author)
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Elastic neutron scattering at 96 MeV
- 2005
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In: Proc. of the Int. Conf. on Nuclear Data for Science and Technology: Santa Fé, New Mexico, USA, September 26-October 1, 2004. ; , s. 853-
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Conference paper (peer-reviewed)
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| 7. |
- Öhrn, A., et al.
(author)
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Measurements of Inelastic Neutron Scattering at 96 MeV from Carbon, Iron, Yttrium and Lead
- 2011
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In: Journal of the Korean Physical Society. - : Korean Physical Society. - 0374-4884 .- 1976-8524. ; 59:2, s. 1817-1820
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Journal article (peer-reviewed)abstract
- Inelastic neutron scattering for (12)C, (58)Fe, (89)Y and (208)Pb have been measured at 96 MeV at the The Svedberg Laboratory in Uppsala and double-differential cross sections are reported. Data cover an excitation energy range of 0-45 MeV and the angular intervals are 28 - 58 degrees for (12)C, 26 - 65 degrees for (58)Fe and 26 - 52 degrees for (89)Y and (208)Pb. In this experiment, neutron detection is based on conversion to protons in an active scintillator converter. An analysis technique in which the neutron spectra have been obtained through a folding procedure using the response of the detector system has been used. The results are compared to and are in reasonable agreement with several model predictions and with inelastic neutron scattering data at 65 MeV from University of California, Davis, USA.
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| 8. |
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| 9. |
- Öhrn, Angelica, et al.
(author)
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Elastic scattering of 96 MeV neutrons from iron, yttrium, and lead
- 2008
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In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 77:2, s. 024605-
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Journal article (peer-reviewed)abstract
- Data on elastic scattering of 96 MeV neutrons from Fe-56, Y-89, and Pb-208 in the angular interval 10-70 degrees are reported. The previously published data on Pb-208 have been extended, as a new method has been developed to obtain more information from data, namely to increase the number of angular bins at the most forward angles. A study of the deviation of the zero-degree cross section from Wick's limit has been performed. It was shown that the data on Pb-208 are in agreement with Wick's limit while those on the lighter nuclei overshoot the limit significantly. The results are compared with modern optical model predictions, based on phenomenology and microscopic nuclear theory. The data on Fe-56, Y-89, and Pb-208 are in general in good agreement with the model predictions.
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