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Technology Name
Briefcase
Scientist
1263
"Spin-optics", a new method for controlling electric current by manipulating electron spin-orbit interaction, can be used in semiconductors to achieve a wider spectrum of functionality similar to that achieved with polarized light. This method may be used for ultra-fast spin-based transistors.

"Spin-optics", a new method for controlling electric current by manipulating electron spin-orbit interaction, can be used in semiconductors to achieve a wider spectrum of functionality similar to that achieved with polarized light. This method may be used for ultra-fast spin-based transistors.

Applications


  • Ultra-fast spin-based field effect transistor (spin-FET) for communications, computing, and defense applications.
  • Nano- and micro-electronic semiconductor devices for polarizing, filtering, switching, guiding, storing, spin detecting and focusing the current carriers.
  • Devices for signal splitting and wide-angle sparging of electrons.

  • Advantages


    • Use of Nou-magnetic semiconductor materials
    • Creation of spin polarize current

    Technology's Essence


    Researchers at the Weizmann Institute of Science have discovered a novel method for controlling and manipulating the propagation of electrons in semiconductors with spin-orbit interaction by acting on the spin polarization of the electrons. It was found that when the spin-orbit coupling strength in the semiconductor is locally varying, electrons of different spin polarizations deflect by different angles at the region of the spin-orbit inhomogeneity. The spin-orbit coupling can be tuned locally and dynamically by applying bias voltage with gates. With suitable angle of incidence of electrons, one spin polarization either can pass through the region of inhomogeneity or totally reflected, in analogy to the total internal reflection phenomenon in optics. In fact, this new approach to spintronics is similar to manipulating polarized light in optical technologies. With this approach (termed "spin-optics") it is possible to manipulate the current carriers in semiconductors (electrons or holes) to achieve the whole spectrum of functionality used in optics of the polarized light, e.g., spin polarizing, spin filtering, switching, guiding as well as spin-based field effect transistor (spin-FET).

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    • Prof. Alexander Finkelstein
    1447
    A cheap and effective solution for protecting RFID tags from power attacks. RFID tags are secure tags present in many applications (e.g. secure passports). They are poised to become the most far-reaching wireless technology since the cell phone, with worldwide revenues expected to reach $2.8 billion in...

    A cheap and effective solution for protecting RFID tags from power attacks.

    RFID tags are secure tags present in many applications (e.g. secure passports). They are poised to become the most far-reaching wireless technology since the cell phone, with worldwide revenues expected to reach $2.8 billion in 2009. RFID tags were believed to be immune to power analysis attacks since they have no direct connection to an external power supply. However, recent research has shown that they are vulnerable to such attacks, since it is possible to measure their power consumption without actually needing either tag or reader to be physically touched by the attacker. Furthermore, this attack may be carried out even if no data is being transmitted between the tag and the attacker, making the attack very hard to detect. The current invention overcomes these problems by a slight modification of the tag's electronic system, so that it will not be vulnerable to power analysis.

    Applications


    • Improved security of RFID tags.

    Advantages


    • Simple and cost-effective
    • The design involves changes only to the RF front-end of the tag, making it the quickest to roll-out


    Technology's Essence


    An RFID system consists of a high-powered reader communicating with a tag using a wireless medium. The reader generates a powerful electromagnetic field around itself and the tag responds to this field. In passive systems, placing a tag inside the reader's field also provides it with the power it needs to operate. According to the inventive concept, the power consumption of the computational element is detached from the power supply of the tag. Thus, the present invention can almost eliminate the power consumption information.

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    • Prof. Adi Shamir
    1529
    We present an efficient and robust broadband crystal optical conversion device. Various applications of laser optics require tunable laser sources. Currently, most frequency conversion devices rely on a single non-linear crystal, which is either temperature or angle tuned to enhance efficiency. This...

    We present an efficient and robust broadband crystal optical conversion device. Various applications of laser optics require tunable laser sources. Currently, most frequency conversion devices rely on a single non-linear crystal, which is either temperature or angle tuned to enhance efficiency. This results only in a narrow efficient spectral band of conversion. Other techniques such as periodic quasi-phase matching result in improved efficiencies but still within a narrow predetermined band. Random quasi-phase matching results in improved bandwidth but in a significant reduction in efficiency. This new device enables ultra-broadband wavelength conversion while maintaining high efficiency.

    Applications


    • Laser optics industry
    • Frequency convertor for broadband signals
    • Generation of ultrafast visible radiation
    • Pulse selection.

    Advantages


    • 90% efficiency of conversion process.
    • Simple and compact
    • Insensitive to the deviations in alignment, no dependence of the angle incidence beam or of temperature
    • Frequency converter of both broadband signals and ultra-short pulses.

    Technology's Essence


    This device is based on a new method of adiabatic wavelength conversion. The device works whereby a strong narrow-band pump is introduced into the crystal along with a weaker pulse to be converted. This conversion is realized in a quasi-phase matched nonlinear crystal, where the period is tuned adiabatically from strong negative phase-mismatch to strong positive phase-mismatch (or vice versa). This results in the efficient transformation of the weaker pulse.

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    • Prof. Yaron Silberberg
    1021
    A method for mapping and correcting optical distortion conferred by live cell specimens in microscopy that cannot be overcome using optical techniques alone can be used both for light microscopy and confocal microscopy. The system determines the 3D refractive index for the samples, and provides a...

    A method for mapping and correcting optical distortion conferred by live cell specimens in microscopy that cannot be overcome using optical techniques alone can be used both for light microscopy and confocal microscopy. The system determines the 3D refractive index for the samples, and provides a method for ray tracing, calculation of 3D space variant point spread, and generalized deconvolution.

    Applications


    Microscopy: The method was developed and applied for light microscopy, and is of critical importance for detection of weak fluorescently labeled molecules (like GFP fusion proteins) in live cells. It may be applicable also to confocal microscopy and other imaging methods like ultrasound, deep ocean sonar imaging, radioactive imaging, non-invasive deep tissue optical probing and photodynamic therapy. Gradient glasses: The determination of the three-dimensional refractive index of samples allows testing and optimization of techniques for production of gradient glasses. Recently continuous refractive index gradient glasses (GRIN, GRADIUM) were introduced, with applications in high quality optics, microlenses, aspherical lenses, plastic molded optics etc. Lenses built from such glasses can be aberration-corrected at a level, which required doublets and triplets using conventional glasses. Optimized performance of such optics requires ray tracing along curved path, as opposed to straight segments between surface borders of homogeneous glass lenses. Curved ray tracing is computation-intensive and dramatically slows down optimization of optical properties. Our algorithm for ray tracing in gradient refractive index eliminates this computational burden.

    Technology's Essence


    A computerized package to process three-dimensional images from live biological cells and tissues was developed in order to computationally correct specimen induced distortions that cannot be achieved by optical technique. The package includes: 1. Three-dimensional (3D) mapping of the refractive index of the specimen. 2. Fast method for ray tracing through gradient refractive index medium. 3. Three-dimensional space variant point spread function calculation. 4. Generalized three-dimensional deconvolution.

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    • Prof. Zvi Kam
    1238
    Coherently combining two or more low-power laser beams preserves low-power beam quality while significantly boosting the overall beam power as a function of the number of individual beams. The result is a high-power, high-quality robust laser beam.

    Coherently combining two or more low-power laser beams preserves low-power beam quality while significantly boosting the overall beam power as a function of the number of individual beams. The result is a high-power, high-quality robust laser beam.

    Applications


    Coherent combining of laser beams leads to compact, stable and robust, laser configurations with very high output powers and good beam quality. Such laser configuration could be potentially exploited in many important medical and industrial applications. These include laser material processing, such as laser welding and laser cutting, laser surgery and laser pollution monitoring.

    Technology's Essence


    At the Weizmann Institute of Science, a team of researchers developed a novel approach for intra-cavity phase locking and coherent addition of two or more laser beam distributions. This includes the phase locking and coherent addition of Gaussian distributions, single high-order mode distributions, and even spatially incoherent multimode distributions. In their approach the phase locking and coherent addition is achieved using new interferometric and polarization couplers/combiners with a variety of laser configurations. The laser configurations are compact and robust, enabling stable operation under harsh environmental conditions. Some successful preliminary experiments were performed with pulsed Nd:YAG lasers. In these experiments phase locking and coherent addition of several laser distributions were demonstrated, with more than 95% combining efficiency and excellent beam quality. The overall configuration was found to be very stable and insensitive to geometrical displacements of the combiner coupler.

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    • Prof. Asher A. Friesem
    • Prof. Nir Davidson
    1266
    Fast cross-sectioning using multiphoton microscope.  The conventionally used laser-scanning microscopy, confocal and multiphoton microscopy, although being capable of performing optical sectioning, requires a long image acquisition time, tens of milliseconds per section in current commercial systems,...

    Fast cross-sectioning using multiphoton microscope.  The conventionally used laser-scanning microscopy, confocal and multiphoton microscopy, although being capable of performing optical sectioning, requires a long image acquisition time, tens of milliseconds per section in current commercial systems, due to the scanning process. The field of confocal microscopy relies on the idea of point-by-point illumination of a sample and use mechanical scanning in order to collect an image. Multiphoton microscopes offer a different mechanism for optical sectioning and the need for rejecting out-of-focus scattering is practically eliminated. However, the process is efficient only when the peak intensity of the illuminating light is high. Thus there is a growing need to facilitate the multiphoton microscopy imaging of a sample by providing a novel illumination configuration and method of its operation.

    Depth-resolved microscopy has been, for decades, practically synonymous with laser-scanning microscopy. The technique of the present invention provides for full-frame depth-resolved microscopy (or material processing), using an extremely simple setup as well as standard components, aiming at eliminating mechanical scanning across the sample thus making the image acquisition much faster.

     

    Applications


    • Optical system for use in a multi-photon microscope.
    • Material processing, e.g. simultaneous depth-resolved modification of a transparent substrate by femtosecond radiation.

    Advantages


    • The present invention provides for fast imaging/processing of a sample without scanning.
    • The temporal profile of the pulse remains unchanged as it propagates through the sample.
    • Single-shot depth resolved microscopy is able to capture extremely rapid dynamics, up to the nanosecond regime.
    • The setup enables full-frame video-rate fluorescence lifetime imaging, simply by gating the CCD intensifier.
    • Enables utilization of structure illumination microscopy.
    • Can be used with practically any multiphoton process.

    Technology's Essence


    The present invention provides the ability for illuminating a region of a sample with dimensions many orders of magnitude larger than a diffraction-limited spot of the imaging lens arrangement used in the microscope. Using this method, full-frame depth-resolved microscopy can be achieved using an extremely simple setup and standard components. the proposed microscope utilizes a pulse manipulator arrangement including a temporal pulse manipulator configured to define a surface, which extends perpendicular to the optical axis of a microscope in the front focal plane of an imaging lens arrangement, and which is patterned to affect trajectories of light components of the input short pulse impinging onto different points of this surface to direct these light components along different optical paths.

    This novel invention is not limited to imaging techniques in general and to microscopy in particular and can also be used for material processing.

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    • Prof. Yaron Silberberg

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