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This new result contributes to the international effort to define the second with a much greater level of accuracy than before, enabling new scientific and
Atomic clocks are key to a wide array of technologies and scientific experiments, including tests of fundamental physics. Clocks operating at optical frequencies have now demonstrated fractional stability and reproducibility at 10 -18, two orders of magnitude beyond their microwave predecessors
Until recently, the precision measurement of phase noise, spectral purity, and related quantities had been a challenging process, with only a handful of qualified experts in the world. However, Field Programmable Gate Array (FPGA) based measurement systems, similar to software defined radio (SDR)
Frequency synthesis plays an essential role in virtually all present-day commercial, industrial, and military technologies. State-of-the-art low-noise frequency synthesis is a crucial technical asset to high-resolution imaging and radar, high-speed telecommunications, and efficient management of the
The primary responsibility of the Phase Noise Metrology Group is to develop and provide calibration services for industrial, military, and commercial organizations to support the core mission of NIST. The PM and AM noise measurements require traceability and certification of devices such as phase
Takuma Nakamura, Yifan Liu, Naijun Jin, Haotian Cheng, Charles McLemore, Nazanin Hoghooghi, Peter Rakich, Franklyn Quinlan
We demonstrate thermal noise-limited direct locking of a semiconductor DFB laser to a sub-1 mL volume, ultrastable optical cavity, enabling extremely compact
Archita Hati, Marco Pomponio, Nicholas Nardelli, Tanner Grogan, Kyungtae Kim, Dahyeon Lee, Jun Ye, Tara Fortier, Andrew Ludlow, Craig Nelson
This paper presents a frequency synthesis that achieved exceptional stability by transferring optical signals to the RF domain at 100 MHz. These systems employ
Elizabeth Benham, Kristen Dill, Dinelka Jagoda, Maryanne Amanze, Yoon Thwel
The metric system (International System of Units, SI) is easy to use and learn. The Metric System Estimation Game is a fun, hands-on activity that helps
Matthew Spidell, Malcolm White, Alan Jaffe, John Lehman, Gaylon Partain
DC voltage references are typically based on calibrated Zener Diodes which are subject to drift and therefore require periodic recalibration against a Primary