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A novel sloped field plate (FP)-enhanced ultra-short edge termination structure is proposed and experimentally demonstrated. The structure features a benzocyclobutene dielectric filled trench, and is fabricated along with a high-voltage p-i-n diode. In addition, a sloped FP is put inside the trench and connected to the anode electrode. The fabricated device shows a breakdown voltage of 755 V, and is confirmed as the ideal planar junction breakdown voltage of the p-i-n diode. The proposed edge termination structure has a total width of 35 mu m, which is similar to 1/5 the size of a conventional termination structure using the guard rings approach.

A novel sloped field plate (FP)-enhanced ultra-short edge termination structure is proposed and experimentally demonstrated. The structure features a benzocyclobutene dielectric filled trench, and is fabricated along with a high-voltage p-i-n diode. In addition, a sloped FP is put inside the trench and connected to the anode electrode. The fabricated device shows a breakdown voltage of 755 V, and is confirmed as the ideal planar junction breakdown voltage of the p-i-n diode. The proposed edge termination structure has a total width of 35 mu m, which is similar to 1/5 the size of a conventional termination structure using the guard rings approach.

A novel sloped field plate (FP)-enhanced ultra-short edge termination structure is proposed and experimentally demonstrated. The structure features a benzocyclobutene dielectric filled trench, and is fabricated along with a high-voltage p-i-n diode. In addition, a sloped FP is put inside the trench and connected to the anode electrode. The fabricated device shows a breakdown voltage of 755 V, and is confirmed as the ideal planar junction breakdown voltage of the p-i-n diode. The proposed edge termination structure has a total width of 35 mu m, which is similar to 1/5 the size of a conventional termination structure using the guard rings approach.

Intense ultrafast laser pulses tightly focused in the bulk of transparent material produce plasma in the extreme conditions similar to those in the cores of planets. The plasma generates strong shock waves in such confined geometry, thus inducing a laser-ignited microexplosion. This new method of compression of matter by ultra-short laser induced micro-explosion generates pressures in excess of Terapascals, leaving all the pressure/temperature-affected material confined inside the bulk of pristine crystal for the further investigations

An ultracompact polarization beam splitter (PBS) is proposed based on an asymmetrical directional coupler consisting of a silicon hybrid plasmonic waveguide (HPW) and a silicon nanowire. The widths of the two coupling waveguides are chosen so that the phase-matching condition is satisfied for TE polarization only while the phase mismatch is significant for TM polarization. A sharply bent silicon HPW is connected at the thru port to play the role of polarizer by utilizing its polarization-dependent loss. With the present principle, the designed PBS has a footprint as small as only similar to 1.9 mu m x 3.7 mu m, which is the shortest PBS reported until now, even when large waveguide dimensions (e. g., the waveguide widths w(1,2) = similar to 300 nm and the gap width w(gap) = similar to 200 nm) are chosen to simplify the fabrication process. The numerical simulations show that the designed PBS has a very broad band (similar to 120 nm) with an extinction ratio >12 dB and a large fabrication tolerance to allow a waveguide width variation of similar to 30 nm., QC 20130909

A Reply to the Comment by C. Thaury et al.

Field ionization plays an important role in modeling the interaction of high-power, ultra-short lasers pulses with matter. Many field ionization models exist that have predictive capability at non-relativistic laser intensities and for laser pulse durations that much longer than the atomic time scales. Most existing models take a quasi-static approach to the laser field on atomic dimensions and time scales. Yet, with pulses as short as a few ~10 to ~100 as and intensities of 10 21 W/cm 2 the feasibility of these approximations becomes questionable. Still the exploration of plasma effects in relativistic laser matter interaction requires to test the boundaries of validity for these models. This thesis will take a step to point out the difficulties to be considered when existing ionization models are applied to such extreme cases.

Field ionization plays an important role in modeling the interaction of high-power, ultra-short lasers pulses with matter. Many field ionization models exist that have predictive capability at non-relativistic laser intensities and for laser pulse durations that much longer than the atomic time scales. Most existing models take a quasi-static approach to the laser field on atomic dimensions and time scales. Yet, with pulses as short as a few ~10 to ~100 as and intensities of 10 21 W/cm 2 the feasibility of these approximations becomes questionable. Still the exploration of plasma effects in relativistic laser matter interaction requires to test the boundaries of validity for these models. This thesis will take a step to point out the difficulties to be considered when existing ionization models are applied to such extreme cases.

Laser-plasma wakefield based electron accelerators are expected to deliver ultrashort electron bunches with unprecedented peak currents. However, their actual pulse duration has never been directly measured in a single-shot experiment. We present measurements of the ultrashort duration of such electron bunches by means of THz time-domain interferometry. With data obtained using a 0.5J, 45fs, 800nm laser and a ZnTe-based electro-optical setup we demonstrate the duration of laser-accelerated, quasi-monoenergetic electron bunches at a best fit of 32fs (FWHM) with a 90% upper confidence level of 38fs.

Laser-plasma wakefield based electron accelerators are expected to deliver ultrashort electron bunches with unprecedented peak currents. However, their actual pulse duration has never been directly measured in a single-shot experiment. We present measurements of the ultrashort duration of such electron bunches by means of THz time-domain interferometry. With data obtained using a 0.5J, 45fs, 800nm laser and a ZnTe-based electro-optical setup we demonstrate the duration of laser-accelerated, quasi-monoenergetic electron bunches at a best fit of 32fs (FWHM) with a 90% upper confidence level of 38fs.