Graphene and other two-dimensional materials display remarkable optical properties, including a simple light transparency of $T \approx 1 - \pi \alpha$ for in the visible region. Most theoretical rationalizations this "universal" opacity employ model coupling to electron's crystal momentum put emphasis on linear dispersion graphene bands. However, such formulation interband absorption is not allowable within band structure theory, because it conflates label with canonical operator. We show...

We discuss an application of correlation analysis to surface metrology high quality x-ray optics with the aim elicitation and, when possible, suppression instrumental systematic errors in final results. describe and present mathematical foundation for a novel method consisting randomization error by averaging multiple measurements, specially arranged mutually anti-correlate. also possibility apply entire residual slope distribution order find anti-correlation parameters distribution. In this...

Systematic error and instrumental drift are the major limiting factors of sub-microradian slope metrology with state-of-the-art x-ray optics. Significant suppression errors can be achieved by using an optimal measurement strategy suggested in [Rev. Sci. Instrum. 80, 115101 (2009)]. Here, we report on development automated, kinematic, rotational system that provides fully controlled flipping, tilting, shifting a surface under test. The is to integrated into Advanced Light Source long trace...

We demonstrate a comprehensive and broadly applicable methodology for the optimal in situ configuration of bendable soft x-ray Kirkpatrick-Baez mirrors. The mirrors used this application are preset at Advanced Light Source Optical Metrology Laboratory prior to beamline installation. consists new technique simultaneously setting height pitch angle each mirror. benders both were then optimally tuned order minimize ray aberrations level below diffraction-limited beam waist size 200 nm...

To explore the confinement of high-energy ions above space charge limit, we have developed a hybrid magnetic and electrostatic device called an Orbitron. The Orbitron is crossed-field combining aspects mirrors, magnetrons, orbital ion traps. Ions are confined in orbits around high-voltage cathode with co-rotating electrons by relatively weak field. Experimental computational investigations focus on reaching densities limit through co-confinement electrons. experimental apparatus suite...

Electric deflection measurements on liquid helium nanodroplets doped with individual polar molecules demonstrate that the cold superfluid matrix enables full orientation of molecular dipole along external field. This translates into a force which is increased enormously by comparison typical experiments, and it becomes possible to measurably deflect neutral droplets masses tens hundreds thousands Daltons. approach permits preparation study continuous fluxes fully oriented broadly generally...

Helium nanodroplets doped with polar molecules are studied by electrostatic deflection. This broadly applicable method allows even polyatomic to attain subkelvin temperatures and nearly full orientation in the field. The resulting intense force from field gradient strongly deflects droplets tens of thousands atoms, most massive neutral systems beam "deflectometry." We use deflections extract droplet size distributions. Moreover, since each host according its mass, spatial filtering deflected...

We used cold helium droplets as nano-scale reactors to form and ionize, by electron bombardment charge transfer, aromatic amino acid heterodimers of histidine with tryptophan, methyl-tryptophan, indole. The molecular interaction occurring through an N–H ⋅ N hydrogen bond leads a proton transfer from the indole group tryptophan imidazole in radical cationic environment.

Convenience and cost often lead to synchrotron beamlines where the final bendable Kirkpatrick-Baez focusing pair must relay image different samples at distances e.g., [Proc. FEL2009, 246-249 (2009)] either for experimental chambers, or diagnostics. We present an initial analytical approach, starting from, extending work of Howells et al. [OE 39(10), 2748-62 (2000)] analyze trade-offs between choice mirror, bending couples given, shaped sagittal width optic. Both experimentally in simulation,...

Realizing the experimental potential of high-brightness, next generation synchrotron and free-electron laser light sources requires development reflecting x-ray optics capable wavefront preservation high-resolution nano-focusing. At Advanced Light Source (ALS) beamline 5.3.1, we are developing broadly applicable, high-accuracy, in situ, at-wavelength measurement techniques to surpass 100-nrad slope accuracy for diffraction-limited Kirkpatrick-Baez (KB) mirrors. The methodology relies on a...

We report on a cross-comparison of low-spatial-frequency surface slope and height metrology with super-polished flat X-ray mirror Si substrate fabricated for the Stanford Linear Accelerator Center Linac Coherent Light Source hard system HOMS-3. The overall dimensions 450 × 30 50 mm³ was specified to have radius curvature between 150 km 195 residual (after subtraction best-fit cylinder) variation level 0.1 μrad rms, when measured in tangential direction over clear aperture 380 5...

We extend analytical and numerical methods recently developed at the Advanced Light Source (ALS) optical metrology laboratory (OML) for optimal tuning calibration of bendable x-ray optics based on ex situ measurements with surface slope profilers [Opt. Eng. 48(8), 083601 (2009); Proc. SPIE 8141, 8141-19 (2011)]. minimize rms variation residual deviations from ideal figure. Previously, our adjustment assumed were weighted equally across optic. In this work, we analyze case when mirror length...

We report on hands-on experimental methods developed at the Advanced Light Source (ALS) for optimal tuning of mechanically bendable x-ray mirrors diffraction-limited soft nano-focusing. For ex situ benders beam-line performance, we use a revised version method characteristic functions recently ALS optical metrology laboratory. At-wavelength optics consists series wavefront-sensing tests with increasing accuracy and sensitivity, including modified scanning-slit Hartmann tests. The have been...

Long-range intermolecular forces are able to steer polar molecules submerged in superfluid helium nanodroplets into highly metastable configurations. We demonstrate that the presence of such special structures can be identified, a direct and determinative way, by electrostatic deflection doped nanodroplet beam. The measurement also establishes structures' electric dipole moments. In consequence, introduced approach is complementary spectroscopic studies low-temperature molecular assembly...

The Advanced Light Source (ALS) beamline (BL) 10.3.2 is an apparatus for X-ray microprobe spectroscopy and diffraction experiments, operating in the energy range 2.4–17 keV. performance of beamline, namely spatial resolutions measurements, depends significantly on collimation quality light incident monochromator. In BL end-station, synchrotron source imaged 1:1 onto a set roll slits which form virtual source. from this collimated vertical direction by bendable parabolic cylinder mirror....

In order to fulfill the angular resolution requirements and make performance goals for future NASA missions feasible, it is crucial develop instruments capable of fast precise figure metrology x-ray optical elements further correction surface errors. The Long Trace Profilometer (LTP) an instrument widely used measuring grazing incidence X-ray mirrors. case replicated optics designed astronomy applications, such as mirrors corresponding mandrels have a cylindrical shape their tangential...

We describe a systematic procedure developed for surface characterization of super polished x-ray optical components with an interferometric microscope. In this case, obtaining trustworthy metrology data requires thorough accounting the instrument's aberrations, its spatial resolution, and random noise. analyze cross compare two general experimental approaches to eliminate aberration contribution. The reference approach relies on evaluation successive measurements high quality mirror. so...

When it comes to building short-wavelength optical systems control light at the nano-scale, metrology is foundation, and accuracy bedrock. An inescapable truth in our field that most highly specified elements are wildly aberrated when just slightly misaligned, whether misalignment from surface-figure or mirror-placement errors, imperfect bending, thermal drift, vibration, other various anomalies.

MAESTRO, the Microscopic and Electronic STRucture Observatory, currently under construction at Advanced Light Source (ALS), will be a world premier facility for study of electronic structural properties in situ grown crystals. The new comprised several end-stations, including angle-resolved photoemission spectroscopy, μARPES nARPES electron microscope combined with lowenergy (PEEM/LEEM). Redirection x-ray beam between PEEM/LEEM which are longitudinally separated by 2.5 meters, uses system...

We demonstrate a comprehensive and broadly applicable methodology for the optimal in situ configuration of bendable soft x-ray Kirkpatrick-Baez mirrors. The mirrors used this application are preset at ALS Optical Metrology Laboratory prior to beamline installation. consists new technique simultaneously setting height pitch angle each mirror. benders both were then optimally tuned order minimize ray aberrations level below diffraction-limited beam waist size 200 nm (horizontal) × 100...

Recently, a technique for optimal tuning and calibration of bendable x-ray optics using surface slope data obtained with measuring long trace profiler (LTP) was developed at the Advanced Light Source (ALS) optical metrology laboratory (OML) [Opt. Eng. 48(8), 083601 (2009)]. In this technique, distributions measured different settings bending couples each end flat substrate are used to construct bender characteristic functions. Using regression analysis experimental functions, benders that...