Prof. Adam Wax

Dept. of Biomedical Engineering, Duke University

Wednesday, March 1st , 2017

13:00-14:00

Light refreshments and drinks will be served starting 12:30

Auditorium 011, Engineering Class Room Building,

Faculty of Engineering, Tel-Aviv University

Abstract:

The mechanisms by which cells respond to mechanical stimuli are essential for cell function yet not well understood. Many rheological tools have been developed to characterize cellular viscoelastic properties but these typically require direct mechanical contact, limiting their throughput. We have developed a new approach for characterizing the organization of subcellular structures using a label free, noncontact, single-shot phase imaging method that correlates to measured cellular mechanical stiffness. The new analysis approach measures refractive index variance and relates it to disorder strength. These measurements are compared to cellular stiffness, measured using the same imaging tool to visualize nanoscale responses to flow shear stimulus. The utility of the technique is shown by comparing shear stiffness and phase disorder strength across five cellular populations with varying mechanical properties.  An inverse relationship between disorder strength and shear stiffness is shown, suggesting that cell mechanical properties can be assessed in a format amenable to high throughput studies using this novel, non-contact technique. Further studies will be presented which include examination of mechanical stiffness in early carcinogenic events and investigation of the role of specific cellular structural proteins in mechanotransduction.

Prof. Nikolay V. Vitanov

Sofia University, Bulgaria

Wednesday, February 1st , 2017

13:00-14:00

Light refreshments and drinks will be served starting 12:30

Auditorium 011, Engineering Class Room Building,

Faculty of Engineering, Tel-Aviv University

Abstract:

The technique of composite pulses replaces the single pulse used traditionally for driving a two-state quantum transition by a sequence of pulses with suitably chosen phases, which are used as control parameters for shaping the excitation profile in a desired manner.

Composite pulses produce unitary operations, which combine very high fidelity with robustness to parameter variations. We have developed a pool of composite pulses by using a novel SU(2) approach to design recipes for construction of single-qubit operations, including broadband, narrowband and passband pulses, universal composite pulses, composite adiabatic passage and composite STIRAP, some of which have already been demonstrated in experiments with doped solids. We have also designed efficient and robust composite techniques for construction of highly entangled states, e.g. Dicke and NOON states, and multi-qubit gates, e.g. C-phase, Toffoli, and generally C$^N$-phase gates. In this talk I will also describe applications of the idea of composite sequences beyond quantum physics. These include composite techniques for control of light propagation in waveguides, polarization optics and nonlinear frequency conversion, including recent experimental demonstrations.