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Physical Measurement Laboratory

Time and Frequency Division

Projects/Programs

Displaying 1 - 25 of 34
Long_Feature_Image

Bringing the SI to Global Atmospheric Greenhouse Gas Measurement

Ongoing
This multifaceted program leverages expertise in three complementary technical focus areas- all of which involve SI-traceable measurements of relevant atmospheric species such as carbon dioxide, methane, water vapor and oxygen. The efforts include gravimetrically based preparation of primary
laser technologies

Chip-scale ultraprecise laser technologies

Ongoing
Lasers with high spectral purity are used in a diverse application space, including coherent high-speed communications, physical sensing, and manipulation of quantum systems. Lab bench scale Fabry-Perot cavities based on sophisticated vibration, thermal, and atmospheric isolation have made possible
chip scale atomic beam clock

Compact Cold Atom Instruments

Ongoing
Chip-scale laser cooling This project develops technologies to achieve chip-scale laser cooling, beyond direct miniaturization of existing laboratory techniques. This includes development of the vacuum technology for realizing low power, passively pumped ultra-high vacuum chambers [1,2] and novel
optical clock

Compact strontium optical clock with integrated photonics

Ongoing
The development of a liter-scale apparatus to produce Sr, would enable highly accurate, transportable optical clocks based on their ultra-narrow optical transition. However, straightforward miniaturization of the traditional optical infrastructure necessary to implement multi-step laser cooling has
Compact ultrastable optical references illustration

Compact Ultrastable Optical References

Ongoing
At the heart of any stable laser is a reference cavity resonator. By locking a laser’s frequency to a reference cavity mode, the laser inherits the resonator’s stability. These stable lasers can then be used in various sensing and spectroscopy applications, including in optical atomic clocks and
Cryogenic Photonic Interconnects illustration

Cryogenic Photonic Interconnects

Ongoing
Microwave photonics, where optical systems are employed to transport, filter, generate, or otherwise process microwave and millimeter wave signals, takes advantage of the large bandwidth, low loss, and low noise of optical systems, as well as the long reach of optical fiber interconnects. We are

Femtosecond-Laser Frequency Combs for Optical Clocks

Ongoing
The self-referenced optical frequency comb, which our NIST/University of Colorado collaboration first demonstrated in 1999, ushered in a revolution in optical frequency metrology. The frequency comb made it possible to directly count optical cycles with femtosecond resolution using a compact and
Web interface to control and monitor the servo with interactive blocks

Field Programmable Gate Array (FPGA) Designs for Metrology

Ongoing
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)
infrared starlight

Frequency Comb Calibration of Astronomical Spectrographs

Ongoing
A powerful technique for finding exo-planets is based on measuring the tiny Doppler shifts in the light from a star that is induced by the presence of orbiting planets. While many exo-planets have been discovered using this Doppler radial velocity (RV) technique, it remains a significant technical
CombSpec1

Frequency Comb Spectroscopy

Ongoing
Erbium mode-locked fiber lasers are a mature technology that provide a means to build robust optical frequency combs centered near 1550 nm. One research focus of our group is to extend the optical bandwidth of Er fiber-based combs into the near- to mid-infrared wavelength region of 1000 to 5000 nm
NIST FMAS

Frequency Measurement and Analysis Service (FMAS)

Ongoing
Subscribers to the NIST service receive a complete frequency measurement system which includes everything needed to make precision frequency measurements that are traceable to NIST. An easy-to-read instruction manual makes installation a snap. Once the system is installed, it's easy to get started
nist-on-a-chip illustration

Integrated Optical Atomic Devices

Ongoing
The NIST on a Chip project in the Atomic Devices and Instrumentation group is focused on the development of compact, manufacturable, low power, SI-traceable calibration instruments using atomic vapor cells. We anticipate such devices could be broadly used in industrial settings for in-situ
Cryogenic sapphire optical cavity

Laser Stabilization and Coherence with Optical Resonators

Ongoing
First, coherent laser interrogation of the narrowband electronic ‘clock’ transition is required to realize the very high spectroscopic resolution that make optical clocks so precise. At the same time, phase fluctuations in the laser interrogation can compromise the frequency stability of the optical
laser wavelength

Laser-wavelength conversion with nonlinear photonics

Ongoing
Many sophisticated technologies, including detection and characterization of biological samples, quantum sensing of magnetic and electric fields, time standards based on atomic clocks, and precision metrology, demand versatile laser sources spanning a broad range of wavelengths. Nonlinear optics
5 MHz Graph of phase noise vs. offset frequency showing NIST synthesized signal, Wenzel OXCO, and BVA oscilloquartz.

Low-Phase Noise Frequency Synthesis

Ongoing
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
Fiber magnetometer

Microfabricated Atomic Sensors

Ongoing
Our program aims to develop sensors that can simultaneously achieve high absolute scalar accuracy and vector magnetic field measurement without the need for calibrations. An atomic magnetometer relies on the fundamental constants of nature to translate magnetic fields into a measurable Larmor
Microcombs2

Microresonator Device Research

Ongoing
In the last few years a revolutionary paradigm for optical frequency combs and ultrastable continuous-wave lasers has emerged based on nonlinear optics in optical microresonators. Such microresonator devices can now be realized using millimeter-scale, chip-based photonic integrated circuits
microcombs

Microresonator frequency combs for the NIST-on-a-Chip Program

Ongoing
The invention of optical-frequency combs opened many new applications in photonics from precision timing and ranging to generation of entangled states. They are composed of hundreds to millions of optical modes whose frequencies conform to a simple relationship, ν n = n × f rep +f 0, where n is the
nanophotonic

Nonlinear nanophotonic control of light

Ongoing
Light-matter interactions with nonlinear materials provide a powerful tool for converting optical fields from one state to another. For example, nonlinear wavelength conversion leverages efficient scattering of photons of a single frequency to another, enabling generation of coherent sources across
BO+WKB model

Optical Clock Atomic Structure and Theory

Ongoing
This ticking rate (i.e., frequency) is associated with a transition between two quantum levels of the atom, where each level corresponds to a different configuration of the electrons around the nucleus. Atomic clocks derive their incredible accuracy and precision from the robust nature of atoms
yb optical clock

Yb Optical Lattice Clock

Ongoing
In recent years, optical clocks have achieved performance that is orders of magnitude beyond more traditional atomic clocks utilizing a microwave timebase. A particularly promising type of advanced optical clock is the optical lattice clock. At their heart, these systems use an ensemble of ultracold
lownoisemicrowave

Optical and Microwave Waveform Synthesis

Ongoing
A typical optical frequency comb consists of thousands to millions of phase coherent modes (the "teeth" of the comb) that can all be used to synthesize precisely controlled electromagnetic waveforms. Our main research thrust in this area has been focused on the generation of microwave and millimeter
Image of AM/PM Noise Calibration Standard device made by NIST

Phase and Amplitude Noise Calibration Services

Ongoing
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
Measurement device for signals in the W band (75-110 GHz)

Phase and Amplitude Noise Metrology

Ongoing
The group provides high-precision measurement of electromagnetic signals in the radio-frequency, microwave and optical range. These measurements include phase noise, amplitude noise and perturbations due to vibration and temperature. Such precision measurements support high-value applications such
atom chamber

Portable Optical Lattice Clock

Ongoing
These include a variety of navigation, communication, and remote sensing and imaging applications. The very best atomic clocks today, optical clocks, are among the most precise measurement devices of any kind. For example, the NIST ytterbium optical lattice clock can make frequency or time