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1رسالة جامعية
المؤلفون: O'Neale, Charlotte Alicia Susan
مصطلحات موضوعية: 530.12, QC Physics
الوصف: This thesis presents work towards the realisation of dark solitons in a two-dimensional Bose-Einstein condensate. The technical redesign of two sets of coils, necessary for magnetic trapping of the atom cloud in order to create a condensate, is reported. Two different types of coil technology are presented, discussed, and used. The fabrication of the coils is described, and each set of coils is characterised. Both sets of coils have been installed on the main experiment and are fully operational. A key aspect of this thesis is the development of an optical system capable of achieving resolution on the micrometer scale, which can be used for manipulation of a two-dimensional condensate by the method of phase imprinting. The optical system demagnifes the image on a spatial light modulator and focuses the image on the atom plane. Characterisation of the resolution of the optical system shows that a resolution of 3 µm is achieved. The optical system has successfully been implemented on the main experiment and has been used to manipulate the condensate. A two-dimensional BEC of \(^{87}\)Rb with 31000 atoms and a temperature of 88 nK is realised in a dipole trap of frequencies ω\(_x\) = 2π∙5.8 Hz, ω\(_y\)= 2π∙19.1 Hz, ω\(_z\)= 2π∙269.4 Hz, with gravity being in the z-direction. The method of phase imprinting is used to create the first observed soliton in a 2D BEC. Preliminary analysis of the soliton velocity, width and curvature is presented.
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2تقرير
المؤلفون: Meyer, Nadine, Proud, Harry, Perea-Ortiz, Marisa, O'Neale, Charlotte, Baumert, M., Holynski, M., Kronjäger, Jochen, Barontini, Giovanni, Bongs, Kai
المصدر: Phys. Rev. Lett. 119, 150403 (2017)
مصطلحات موضوعية: Condensed Matter - Quantum Gases, Nonlinear Sciences - Pattern Formation and Solitons
الوصف: We experimentally generate two-dimensional Jones-Roberts solitons in a three-dimensional atomic Bose-Einstein condensate by imprinting a triangular phase pattern. By monitoring their dynamics we observe that this kind of solitary waves are resistant to both dynamic (snaking) and thermodynamic instabilities, that usually are known to strongly limit the lifetime of dark plane solitons in dimensions higher than one. We additionally find signatures of a possible dipole-like interaction between them. Our results confirm that Jones-Roberts solitons are stable solutions of the non-linear Schr\"odinger equation in higher dimensions and promote these excitations for applications beyond matter wave physics, like energy and information transport in noisy and inhomogeneous environments.
الوصول الحر: http://arxiv.org/abs/1609.08504Test
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3دورية أكاديمية
المؤلفون: Meyer, Nadine, Proud, Harry, Perea-Ortiz, Marisa, O'Neale, Charlotte, Baumert, Mathis, Holynski, M, Kronjaeger, Jochen, Barontini, Giovanni, Bongs, Kai
مصطلحات موضوعية: QC Physics
الوصف: Jones-Roberts solitons are the only known class of stable dark solitonic solutions of the non-linear Schr\"odinger equation in two and three dimensions. They feature a distinctive elongated elliptical shape that allows them to travel without change of form. By imprinting a triangular phase pattern, we experimentally generate two-dimensional Jones-Roberts solitons in a three-dimensional atomic Bose-Einstein condensate. We monitor their dynamics observing that this kind of solitons is indeed not affected by dynamic (snaking) or thermodynamic instabilities, that instead make other classes of dark solitons unstable in dimensions higher than one. We additionally find signatures of a possible dipole-like interaction between them. Our results confirm the prediction that Jones-Roberts solitons are stable solutions of the non-linear Schr\"odinger equation and promote them for applications beyond matter wave physics, like energy and information transport in noisy and inhomogeneous environments.
وصف الملف: application/zip
العلاقة: http://edata.bham.ac.uk/27/1/data_3c.datTest; Meyer, Nadine and Proud, Harry and Perea-Ortiz, Marisa and O'Neale, Charlotte and Baumert, Mathis and Holynski, M and Kronjaeger, Jochen and Barontini, Giovanni and Bongs, Kai (2017). Observation of two-dimensional localised Jones-Roberts solitons in Bose Einstein condensates. University of Birmingham. Dataset. https://doi.org/10.25500/eData.bham.00000027Test .
الإتاحة: https://doi.org/10.25500/eData.bham.00000027Test
http://edata.bham.ac.uk/27Test/
http://edata.bham.ac.uk/27/1/data_3c.datTest -
4رسالة جامعية
المؤلفون: O’Neale, Charlotte Alicia Susan
المساهمون: Bongs, Kai, na
مصطلحات موضوعية: QC Physics
الوصف: This thesis presents work towards the realisation of dark solitons in a two-dimensional Bose-Einstein condensate. The technical redesign of two sets of coils, necessary for magnetic trapping of the atom cloud in order to create a condensate, is reported. Two different types of coil technology are presented, discussed, and used. The fabrication of the coils is described, and each set of coils is characterised. Both sets of coils have been installed on the main experiment and are fully operational. A key aspect of this thesis is the development of an optical system capable of achieving resolution on the micrometer scale, which can be used for manipulation of a two-dimensional condensate by the method of phase imprinting. The optical system demagnifes the image on a spatial light modulator and focuses the image on the atom plane. Characterisation of the resolution of the optical system shows that a resolution of 3 µm is achieved. The optical system has successfully been implemented on the main experiment and has been used to manipulate the condensate. A two-dimensional BEC of \(^{87}\)Rb with 31000 atoms and a temperature of 88 nK is realised in a dipole trap of frequencies ω\(_x\) = 2π∙5.8 Hz, ω\(_y\)= 2π∙19.1 Hz, ω\(_z\)= 2π∙269.4 Hz, with gravity being in the z-direction. The method of phase imprinting is used to create the first observed soliton in a 2D BEC. Preliminary analysis of the soliton velocity, width and curvature is presented.
وصف الملف: application/pdf
العلاقة: http://etheses.bham.ac.uk//id/eprint/5707/1/O%E2%80%99Neale15PhD.pdfTest; O’Neale, Charlotte Alicia Susan (2015). Towards solitons in a 2D BEC apparatus. University of Birmingham. Ph.D.
