Monochromator.us

Let there be light! Fiat lux!

Using extreme ultraviolet light

    Earlier this summer NATURE published a nice paper* from the Gedik group at MIT. Briefly, and from the paper's Abstract: "Our technique can produce tunable photon energy between 24–33 eV with an unprecedented energy resolution of 30 meV and time resolution of 200 fs. This technique enables time-, energy- and momentum-resolved investigation of the non-equilibrium dynamics of electrons in materials with a full access to their first Brillouin zone"

    And more, from Phys.Org online "the newly developed XUV trARPES setup at MIT, which is approximately 10 feet long, can generate a femtosecond extreme ultraviolet light source at high energy resolution. "XUV will be quickly absorbed by air, so we house the optics in vacuum," Sie says. "Every component from the light source to the sample chamber is projected on the computer drawing on a millimeter precision." This technique enables full access to the electronic band structure of all materials with unprecedentedly narrow energy resolution on femtosecond timescales. "To demonstrate the resolution of our setup, it is not sufficient to measure the resolution of the light source alone," Sie says. "We must verify the true resolutions from real photoemission measurements using a wide range of materials—the results are very satisfying!"

     experimental layout for high harmonic generation (HHG)

    * Sie, E.J., Rohwer, T., Lee, C. et al. Time-resolved XUV ARPES with tunable 24–33 eV laser pulses at 30 meV resolution. Nat Commun 10, 3535 (2019) doi:10.1038/s41467-019-11492-3

f/4.7 VUV and IR Monochromator

    The McPherson Model 207 is the best spectrometer when you need high-brightness over a broad spectral range. With the use of custom, gold-coated optics or MgF2 coatings optimized for the UV, it excels at measurements from the deep UV, through visible wavelengths, into the long-wave infrared. The Model 207V (a vacuum version) even allows use into the VUV and Vacuum IR wavelengths. Both versions of the Model 207 are ideal instruments for use in tunable light source systems for illumination, imaging, and spectroscopy.

    A fast spectrometer is essential to collect light in both the VUV and the IR regimes of the spectrum. Whether the spectrometer is being used as a light source to deliver the most light possible or is used to collect a signal, the higher collection efficiency of faster f number and optimized optics coating is essential. This makes the Model 207 and the Model 207V ideal spectrometers for experiments conducted in the VUV or the IR.

    The new Model 207 is a 670mm focal length, optically fast, f/4.7 monochromator. The Model 207 is available in a VUV version for use down to 105nm and in the vacuum IR. It is also now available with off-axis parabolic optics for better imaging, if required. The off-axis parabolic (OAP) mirrors provide both low f/number and stigmatic monochromator performance. The Model 207A with OAP optics provides coincident sagittal and tangential foci as well as perfect collimation and focusing, which is beneficial in source systems. The combination of OAP with either the Model 207 or the Model 207V make this an ideal system for small compact images, such as for use in Raman, with small laser exited sources, or with imaging detectors.

    The McPherson Model 207 is the best spectrometer when you need high-brightness over a broad spectral range. With the use of custom, gold-coated optics or MgF2 coatings optimized for the UV, it excels at measurements from the deep UV, through visible wavelengths, into the long-wave infrared. The Model 207V (a vacuum version) even allows use into the VUV and Vacuum IR wavelengths. Both versions of the Model 207 are ideal instruments for use in tunable light source systems for illumination, imaging, and spectroscopy.

    Other features include Snap-In™ diffraction gratings optimized for spectral resolution and/or for wavelength range coverage. Gratings are available to cover wavelength ranges from 105 nm to 100 μm! For CCD’s, it has an accessible 50-millimeter wide focal plane and precise and durable slits for coupling free-space or fiber optics.

    Researchers who need versatile high-brightness as a tunable light source for diagnostic or analytical spectroscopy use the Model 207. Call McPherson for a consultation today. We can help you customize your spectrometer for your specific application.

Tunable Soft X-ray Light Source

    The new 642-1 Soft X-Ray (SXR) light source from McPherson features a six position anode carousel. Users can easily change anode target materials while in high, or even ultra-high vacuum (UHV). Use of different solid target anode materials allows tuning emission eV energy or wavelength to the experiment. The vacuum housing of the source features standard NW40K vacuum flanges (optionally DN40CF). It also features two equivalent output beams. These provide ability for sample/reference comparison and device calibration. Filter wheels, gate valves, pinhole collimators, and energy- or other standard detectors are also available.

    This electron impact light source uses a hot filament to produce electrons subsequently accelerated towards a solid anod target by high voltage. The SXR and extreme UV output emission spectrum follows the target anode material valence band structure. Readily exchange anodes in the carousel in order to produce desired wavelengths, for example Si (0.71 nm), Mg (0.98 nm), C (4.4 nm) and many more. Many different anodes are available! This source is different from other sealed single wavelength x-ray tubes, because a selection of materials are installed in the evacuated housing at one time.

    The new controller for the SXR source provides emission loop regulation for control of the filament and high voltage. One easily operated controller drives source parameters and allows adjusting high-voltage to 10,000 volts and current up to 10 milliamps. The new source is compact and controllable, output is debris free. Stable operation is attained with vacuum of 5 x 10E-5 torr or lower. The McPherson Model 642-1 is easy to set up and provides laboratories excellent, reliable means for at-wavelength calibration, or metrology of SXR lithography materials as well as multilayer or grazing incidence optical systems for astrophysics and other fundamental research. The source is available on special order with powers high as 300 Watts.

    McPherson, Inc. (Chelmsford, MA USA) manufactures a variety of instruments that measure and tune specific wavelengths of light for many disciplines of spectroscopy. The company delivers instrumentation to domestic and international laboratories for fundamental research in optics, physics, and chemistry. To learn more about our instruments and custom manufacturing capabilities, visit

McPhersonInc.com or call 1-978-256-4512 today.

Some 2019 events

VUVX 2019 Meeting in San Francisco
  • Visit booth #8 at the 40th International Conference on Vacuum Ultraviolet and X-ray Physics July 1-5 in San Francisco. This VUVX 2019 meeting is at the Westin St. Francis Hotel in the heart of San Francisco. VUVX caters to scientists from around the world whose work employs electromagnetic radiation in the spectral range from vacuum ultraviolet to hard X-ray radiation from synchrotron, laser, and plasma based sources. Presentations cover instrumentation, methods development, and novel applications in physics, material science, chemistry, biology, and technology. The meeting is hosted by Lawrence Berkeley National Laboratory

Atomic, molecular, and optical physics and instrumentation