The purpose of this contract is to develop and deliver to the National Institute of Standards and Technology (NIST) high-efficiency, low-dark-count detectors for single photons of 1.55 micron wavelength. NIST seeks improved near-infrared (NIR) photon-counting detectors to support emerging quantum information applications in which information is encoded into, for example, the polarization state of single photons. This includes quantum computation and cryptography. The detectors being developed by Voxtel under this contract have the potential to count single photons at a rate roughly 2 orders of magnitude faster than existing technology, and can therefore support faster quantum bit rates. However, Voxtel's single photon detector technology is new, and although it supports faster bit rates than existing technology, the error rate is also higher. Voxtel's single photon detector technology will be improved during the course of this contract to lower its error rate, culminating in delivery of QTY 10 functioning prototype detectors to NIST at the end of the program. The deliverable detectors will have multi-mode fiber pigtails for convenience of use by NIST scientists. Final performance goals for the new detectors are a maximum count rate of 100 MHz with an error rate of 1 kHz and a single photon detection efficiency of 35% at 1550 nm. It will also be possible to operate the detectors with higher detection effiency at the expense of higher error rate, so users can optimize the operating point for their application.