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Full-Text Articles in Statistical, Nonlinear, and Soft Matter Physics

Non-Hermitian Matter-Wave Mixing In Bose-Einstein Condensates: Dissipation-Induced Amplification, S. Wuster, Ramy El-Ganainy Jul 2018

Non-Hermitian Matter-Wave Mixing In Bose-Einstein Condensates: Dissipation-Induced Amplification, S. Wuster, Ramy El-Ganainy

Ramy El-Ganainy

We investigate the nonlinear scattering dynamics in interacting atomic Bose-Einstein condensates under non-Hermitian dissipative conditions. We show that, by carefully engineering a momentum-dependent atomic loss profile, one can achieve matter-wave amplification through four-wave mixing in a quasi-one-dimensional nearly-free-space setup—a process that is forbidden in the counterpart Hermitian systems due to energy mismatch. Additionally, we show that similar effects lead to rich nonlinear dynamics in higher dimensions. Finally, we propose a physical realization for selectively tailoring the momentum-dependent atomic dissipation. Our strategy is based on a two-step process: (i) exciting atoms to narrow Rydberg or metastable excited states, and (ii) introducing …


Modeling Out-Of-Plane Actuation In Thin-Film Nematic Polymer Networks: From Chiral Ribbons To Auto-Origami Boxes Via Twist And Topology, Vianney Gimenez-Pinto, Fangfu Ye, Badel Mbanga, Jonathan Selinger, Robin Selinger Mar 2017

Modeling Out-Of-Plane Actuation In Thin-Film Nematic Polymer Networks: From Chiral Ribbons To Auto-Origami Boxes Via Twist And Topology, Vianney Gimenez-Pinto, Fangfu Ye, Badel Mbanga, Jonathan Selinger, Robin Selinger

Jonathan Selinger

Various experimental and theoretical studies demonstrate that complex stimulus-responsive out-of-plane distortions such as twist of different chirality, emergence of cones, simple and anticlastic bending can be engineered and pre-programmed in a liquid crystalline rubbery material given a well-controlled director microstructure. Via 3-d finite element simulation studies, we demonstrate director-encoded chiral shape actuation in thin-film nematic polymer networks under external stimulus. Furthermore, we design two complex director fields with twisted nematic domains and nematic disclinations that encode a pattern of folds for an auto-origami box. This actuator will be flat at a reference nematic state and form four well-controlled bend distortions …


Application Of Transfer Matrix Method To Secondharmonic Generation In Nonlinear Photonic Bandgap Structures: Oblique Incidence, Han Li May 2015

Application Of Transfer Matrix Method To Secondharmonic Generation In Nonlinear Photonic Bandgap Structures: Oblique Incidence, Han Li

Han Li

No abstract provided.


Sucralose Destabilization Of Protein Structure, Christina M. Othon Mar 2015

Sucralose Destabilization Of Protein Structure, Christina M. Othon

Christina M Othon

Sucralose is a commonly employed artificial sweetener that behaves very differently than its natural disaccharide counterpart, sucrose, in terms of its interaction with biomolecules. The presence of sucralose in solution is found to destabilize the native structure of two model protein systems: the globular protein bovine serum albumin and an enzyme staphylococcal nuclease. The melting temperature of these proteins decreases as a linear function of sucralose concentration. We correlate this destabilization to the increased polarity of the molecule. The strongly polar nature is manifested as a large dielectric friction exerted on the excited-state rotational diffusion of tryptophan using time-resolved fluorescence …


Second-Harmonic Generation At Oblique Angles In Photonic Bandgap Structures, Han Li Jan 2015

Second-Harmonic Generation At Oblique Angles In Photonic Bandgap Structures, Han Li

Han Li

No abstract provided.


Second Harmonic Generation At Oblique Angles In Photonic Bandgap Structures, Han Li Jan 2015

Second Harmonic Generation At Oblique Angles In Photonic Bandgap Structures, Han Li

Han Li

No abstract provided.


Heterogeneous Rotational Diffusion Of A Fluorescent Probe In Lipid Monolayers, Christina M. Othon Aug 2014

Heterogeneous Rotational Diffusion Of A Fluorescent Probe In Lipid Monolayers, Christina M. Othon

Christina M Othon

The rotational correlation time of the lipid probe 1-palmitoyl-2-{6-[(7-nitro-2-1,3-benzoxadiazol-4-yl)amino]hexanoyl}-sn-glycero-3-phosphocholine (NBD-PC) is measured using fluorescence anisotropy for two lipid species. We measure the rotational diffusion in a monolayer of 1,2-Didecanoyl-sn-glycero-3-phosphocholine (DPPC) which displays a phase transition at room temperature from the liquid expanded to the liquid-condensed phase. The constant rotational diffusion of the probe throughout the phase transition reflects the measurement of dynamics in only the liquid-expanded phase. We contrast the dynamic changes during this phase coexistence to the continuous density increase observed in 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) at room temperature. We observe a non-exponential decay of the probe diffusion consistent with heterogeneity …


Electrical Current In Sinai Billiards Under General Small Forces, Pengfei Zhang Dec 2012

Electrical Current In Sinai Billiards Under General Small Forces, Pengfei Zhang

Pengfei Zhang

No abstract provided.


Application Of The Transfer Matrix Method To Reflection Gratings In Positive And Negative Index Materials, Han Li Oct 2012

Application Of The Transfer Matrix Method To Reflection Gratings In Positive And Negative Index Materials, Han Li

Han Li

No abstract provided.


Algebraic Characteristics And Satisfiability Threshold Of Random Boolean Equations, Binghui Guo Dr, Wei Wei Dr, Yifan Sun Dr, Zhiming Zheng Dr Jun 2010

Algebraic Characteristics And Satisfiability Threshold Of Random Boolean Equations, Binghui Guo Dr, Wei Wei Dr, Yifan Sun Dr, Zhiming Zheng Dr

Yifan Sun

No abstract provided.