The Materials Science beamline at the Swiss Light Source has been operational since 2001. In late 2010, the original wiggler source was replaced with a novel insertion device, which allows unprecedented access to high photon energies from an undulator installed in a medium-energy storage ring. In order to best exploit the increased brilliance of this new source, the entire front-end and optics had to be redesigned. In this work, the upgrade of the beamline is described in detail. The tone is didactic, from which it is hoped the reader can adapt the concepts and ideas to his or her needs.

Synchrotron-based X-ray Tomographic Microscopy (SRXTM) is nowadays a powerful technique for non-destructive, high-resolution investigations of a broad kind of materials. High-brilliance and high-coherence third generation synchrotron radiation facilities allow micrometer and sub-micrometer, quantitative, three-dimensional imaging within very short time and extend the traditional absorption imaging technique to edge-enhanced and phase-sensitive measurements. At the Swiss Light Source TOMCAT, a new beamline for TOmographic Microscopy and Coherent rAdiology experimenTs, has been recently built and started regular user operation in June 2006. The new beamline get photons from a 2.9 T superbend with a critical energy of 11.1 keV. This makes energies above 20 keV easily accessible. To guarantee the best beam quality (stability and homogeneity), the number of optical elements has been kept to a minimum. A Double Crystal Multilayer Monochromator (DCMM) covers an energy range between 8 and 45 keV with a bandwidth of a few percent down to 10 −4 . The beamline can also be operated in white-beam mode, providing the ideal conditions for real-time coherent radiology. This article presents the beamline design, its optical components and the endstation. It further illustrates two recently developed phase contrast techniques and finally gives an overview of recent research topics which make intense use of SRXTM.

manufacturable, high throughput process. Currently, In this paper, we present the latest advancements 75 mm diameter InP substrates are used and EBL of sub 50 nm InGaAs/InAlAs/InP High Electron lithography requires less than 1 hour for exposure Mobility Transistor (InP HEMT) devices that have over the wafer. A maximum wafer throughput of 150 achieved extrapolated Fmax above 1 THz. This wafers per week and 100 wafers per week on 100 mm extrapolation is both based on unilateral gain (1.2 diameter wafers would be possible on a single EBL THz) and maximum stable gain/maximum available system. A 2nd key enhancement is the reduction of gain (1.1 THz) extrapolations, with an associated fT of ohmic contact resistance through a higher doped cap 385 GHz. This extrapolation is validated by the layer design coupled with a InAs/InGaAs channel demonstration of a 3-stage common source low noise grown by molecular beam epitaxy. The sheet MMIC amplifier which exhibits greater than 18 dB gain resistance of the epitaxial layers is lowered to 75 at 300 GHz and 15 dB gain at 340 GHz. ohm/sq. (compared to 110 ohm/sq. in the baseline InP HEMT profile) and the mobility was improved to as INTRODUCTION high as 15,000 cmA2N-sec (compared to 12,000 Future systems will extend the need for higher cmA2/V-sec in the baseline InP HEMT profile). A low frequency and bandwidth devices and circuits beyond contact resistance of 0.05 ohm-mm and a high peak current capability and concepts. Rapid development transconductance as high as 2300 mS/mm was and advancement of solid state transistor and MMIC measured at 1V drain bias with a device breakdown technology has pushed extremely high cutoff typically of 2.5V and a maximum drain source voltage frequency and high maximum oscillation frequencies of 2V and good device pinchoff characteristics. (Fmax) in various technologies [1][2][3]. This paper describes the latest advancements of sub 50 nm InP HEMT DEVICE MEASUREMENTS InGaAs/InAlAs/InP High Electron Mobility Transistor S-parameter measurements on extended (InP HEMT) devices that have achieved extrapolated reference plane 2 finger 20 um grounded CPW Fmax above 1 THz for the first time to the best of our devices with 2-mil thick substrates were measured knowledge and is validated by the demonstration of a from 1-110 GHz. The grounded CPW and extended 3-stage low noise MMIC amplifier at 340 GHz with reference plane serve to reduce measurement and greater than 15 dB gain. calibration issues such as probe coupling and substrate modes. The device performance is deInP HEMT DEVICE FABRICATION embedded using an EM simulated SOLT calibration To develop the THz Fmax InP HEMT device, structures fabricated on-wafer. H21 and maximum several process enhancements were implemented on stable gain (MSG) are relatively smooth and follows NGST's baseline InP HEMTs [4]. One key process the theoretical slope of -20 dB/decade and -10 enhancement was the reduction of gate length from dB/decade slope closely from 1 -110 GHz. The 70 to less than 50 nm. Based on cross sections ext...

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The renewed interest of mechanochemistry as an ecofriendly synthetic route has inspired original methodologies to probe reactions, with the aim to rationalize unknown mechanisms. Recently, Friščić et al. ( Nat. Chem. 2013 , 5 , 66 - 73 , DOI: 10.1038/nchem.1505 ) monitored the progress of milling reactions by synchrotron X-ray powder diffraction (XRPD). For the first time, it was possible to acquire directly information during a mechanochemical process. This new methodology is still in its early stages, and its development will definitively transform the fundamental understanding of mechanochemistry. A new type of in situ ball mill setup has been developed at the Materials Science beamline (Swiss Light Source, Paul Scherrer Institute, Switzerland). Its particular geometry, described here in detail, results in XRPD data displaying significantly lower background and much sharper Bragg peaks, which in turn allow more sophisticated analysis of mechanochemical processes, extending the limits of the technique.

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In this letter, the first packaged THz solid-state amplifier operating at 0.85 THz is reported. The InP HEMT amplifier achieves a noise figure as low as 11.1 dB with an associated gain of 13.6 dB at 0.85 THz using high InP HEMT transistors in a 10-stage coplanar waveguide integrated circuit. Output power up to 0.93 mW is measured. Index Terms-Coplanar waveguide (CPW), HEMT, low noise amplifier (LNA), MMIC, MM-Wave, sub-millimeter wave.