SB134117RQ0618_SOW.docx

STATEMENT OF WORK

TITLE: Procurement of a GHz-THz Spectrometer LAB REQUESTING SERVICE: Material Measurement Laboratory, Biomolecular Measurement Division

I. BACKGROUND INFORMATION

Biomaterials Group of Division 644 / MML is involved in the development of measurement methodologies for predicting protein stability in frozen and freeze-dried format. This work involves measurement of ps-ns dynamics of powders and frozen solids through quasi-elastic light scattering. For this purpose, a light-scattering instrument with spectral range of 1 THz and resolution of approximately 1 GHz, and very high rejection of elastically scattered light (~10^14) is required.

Low frequency spectrometers are typically based on interferometry. While interferometers are common optical components for many applications, including distance ranging, laser wavelength tracking, optical fiber-splice inspection, Fourier-transform infrared (FTIR) spectroscopy, optical surface flatness, and others. The requirement for the interferometer to be used in the present application is that it be either tunable so that only certain spectrally resolved components of the light can be detected at once, or dispersive so that all quasielastically scattered light can be detected simultaneously, but with high spectral resolution. The former approach is implemented with differentially scanned dual Fabry-Perot interferometers (FPIs), and latter approach is implemented with virtual image plane arrays (VIPAs). Detecting all quasielastically scattered light simultaneously (with a VIPA) is much more efficient, but no VIPA-based design has yet been able to achieve the high elastic light rejection (rejection ratio > = 1014) needed for the present application.

In order to achieve the required elastic light rejection, multiple passes are made through the tandem FPIs, each having high finesse. Typically, flat FPIs are used, but these are difficult to align. Confocal FPIs are much easier to align and use, but a constraint of confocal FPIs is that the free spectral range (FSR) is fixed by the mirror curvature, and they can be tuned through only one FSR. An extended joint FSR can be achieved from tandem confocal FPIs if the FSR of the individual confocal FPIs are chosen correctly. The joint FSR is given as the least common multiple (LCM) of the two individual FSRs. For example, if the FSR of one confocal FPI is 1,498 MHz, and the other is 1,469 MHz, the joint FSR will be 2.2 THz. Of course, the FSRs of the individual FPIs must differ by at least several times the resolution of the individual FPIs.

A further difficulty with confocal FPIs is that multiple passes typically require spatially distinct interferometer modes through which to pass the light. Confocal FPIs with curvature small enough to accommodate several passes will typically have a FSR on the order of a few GHz or less, and a resolution on the order of MHz. Given the low scattering levels, such narrow resolution will likely result in counts below the detector noise level. It is expected that broader resolution, on the order of GHz is required so that signal at the detector will be above noise.

II. SCOPE OF WORK

The Contractor shall provide one (1) analytical instrument system that meets the following minimum technical requirements. The Contractor shall provide instructions for installing and operating the instrument as described below.

III. SPECIFICATIONS

System Requirements:

The Spectrometer:

· Must be a bench-top, low-frequency spectrometer

· Must provide spectral coverage from 1 GHz to 1 THz, with 1 GHz resolution or better

· Must provide means for automated tuning through a desired spectral range, if the instrument is a scanning spectrometer

· Must be able to reject inelastically scattered light at the level of 10^14 rejection ratio

· Must employ a proven design to achieve required resolution and rejection examples, such as

· Multi-pass tandem Fabry-Perot interferometer

· VIPA spectrometer with proven elastic light rejection approach

· Must utilize 532 nm light from either

· a Government-furnished Coherent Verdi laser with 532 nm central wavelength, 1 MHz bandwidth, and 100 MHz spectral stability

· a 532 nm, narrow bandwidth laser furnished by the contractor

· If a multi-pass tandem Fabry-Perot interferometer, must include a detector with quantum efficiency of at least 60% at 532 nm, and dark counts of no more than 10 counts per second

· Must include protocols for alignment and operation of spectrometer

· Must include protocols for determining absolute frequency difference between excitation laser and light being measured The Software

· Any software package that is included must be included that provides control of the FPI hardware and reads the output of the detector, registering it with the frequency shift at which the FPI is set.

Manual

· The system must include an operations and maintenance manual covering proper alignment, operation, routine maintenance, and trouble-shooting for the instrument and controlling software

· The manual may be supplied in hard copy or electronic format (or both).

Installation:

NIST staff will install the instrument following written guidance from the Contractor.

Warranty:

The Contractor shall provide, at a minimum, a one-year warranty for the equipment. The warranty shall cover all parts, labor and travel. The warranty shall commence upon successful completion of delivery and acceptance.

Training:

Training must be provided for up to 2 NIST personnel covering normal operation, troubleshooting, and routine maintenance. Training may be provided remotely through web-based interaction, or at NIST. If at NIST, training will occur during normal business hours, between 8:30am and 5:00pm Eastern Time, Monday through Friday, except Federal Holidays, and will be coordinated with the NIST Technical Point of Contact (TPOC) to ensure maximum availability of NIST personnel. Training is to occur within 10 days of installation. The training may be completed on-site at NIST immediately after installation and demonstration of specifications.

IV. PERIOD OF PERFORMANCE

All deliverables shall be received by the Government within 70 days from award.

V. PLACE OF PERFORMANCE

All work shall be completed at the Contractor’s facility.

VI. GOVERNMENT FURNISHED PROPERTY

Coherent Verdi V10 is available as an excitation source.

VII. DELIVERABLES

VIII. ACCEPTANCE CRITERIA AND PAYMENT

NSIT staff will determine that the spectral resolution and elastic scattered light rejection specifications are met.

Advance payment is not authorized. The contractor may invoice after Government receipt and acceptance has occurred.