Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: John Kitching (Fed)

Displaying 201 - 225 of 431

Zero-field remote detection of NMR with a microfabricated atomic magnetometer

February 19, 2008

Author(s)

M Ledbetter, I Savukov, D Budker, V Shah, Svenja A. Knappe, John E. Kitching, D Michalak, S Xu, A Pines

We demonstrate remote detection of nuclear magnetic resonance (NMR) with a microfabricated atomic magnetometer and microfluidic channel integrated on a single device. Detection occurs at zero magnetic field, which allows operation of the magnetometer in

Rubidium Vapor Cell with Integrated Nonmetallic Multilayer Reflectors

January 13, 2008

Author(s)

M A. Perez, U Nguyen, A Shkel, Svenja A. Knappe, Elizabeth A. Donley, John E. Kitching

This paper reports on a method for improving the optical efficiency of micromachined reflectors for use in rubidium vapor cells. A hybrid bulk micromachining / multilayer thin film technique is used to form the integrated reflectors, which can redirect

Subpicotesla atomic magnetometry with a microfabricated vapour cell

November 1, 2007

Author(s)

V Shah, Svenja A. Knappe, P Schwindt, John E. Kitching

Highly sensitive magnetometers, capable of measuring magnetic fields below 1 pT, impact areas as diverse as geophysical surveying1, the detection of unexploded ordinance, space science3, nuclear magnetic resonance (NMR), and perimeter and remote monitoring

Time for a Better Receiver: Chip-Scale Atomic Frequency References

November 1, 2007

Author(s)

John E. Kitching

Atomic clocks and precision timing are at the core of almost every aspect of global navigation satellite systems (GNSS). A GNSS receiver determines its position with respect to a subset of the constellation of orbiting satellites by measuring the time

Non-Contact Measurement of Cardiac Electromagnetic Field in Mice Using a Microfabricated Atomic Magnetometer

September 30, 2007

Author(s)

B Lindseth, P Schwindt, John E. Kitching, D Fischer, V Shusterman

The development of clinical applications of magnetocardiography has been impeded by the large size of the magnetic-field measurement systems. Here we present the first measurements of the cardiac electromagnetic field with an ultra-small (2mm), atomic

Advances in Chip-Scale Atomic Frequency References at NIST

September 12, 2007

Author(s)

Svenja A. Knappe, V Shah, Alan Brannon, Vladislav Gerginov, Hugh Robinson, Z Popovic, Leo W. Hollberg, John E. Kitching

We present new advances in the development of chip-scale atomic frequency references. Coherent population trapping (CPT) resonances usually exhibit contrasts below 10 %, when interrogated with frequency modulated lasers. A relatively simple way to increase

Demonstration of high-performance chip-scale magnetic shields

August 14, 2007

Author(s)

Elizabeth A. Donley, Eleanor Hodby, Leo W. Hollberg, John E. Kitching

We have designed and tested a set of five miniature nested magnetic shields constructed of high-permeability material, with volumes ranging from 0.01 to 2.5 cm^3. We present measurements of the longitudinal and transverse shielding factors (the ratio of

Differential Atomic Magnetometry Based on a Diverging Laser Beam

July 3, 2007

Author(s)

Eleanor Hodby, Elizabeth A. Donley, John E. Kitching

We demonstrate a novel atomic magnetometer that uses differential detection of the spatially diverging components of a light field to monitor the Larmor precession frequency of atoms in a thermal vapor. The design is implemented in compact form with a

Generation of coherent population trapping resonances with nearly 100% transmission contrast

May 29, 2007

Author(s)

V Shah, Svenja A. Knappe, Leo W. Hollberg, John E. Kitching

We demonstrate a simple setup for observing very high contrast coherent population trapping resonances in rubidium-87. The high contrast is achieved by eliminating the DC-light background through polarization and spectral filtering.

Self-Injection Locking of a Low-Power Microwave Oscillator by Using 4-Wave Mixing in an Atomic Vapor

May 29, 2007

Author(s)

Alan Brannon, Vladislav Gerginov, V Shah, Svenja A. Knappe, Z Popovic, Leo W. Hollberg, John E. Kitching

We demonstrate self-injection locking of a compact microwave oscillator by using feedback generated from four-wave mixing in an atomic vapor. The four-wave mixing process creates an effective microwave filter with extremely high off-resonant signal

High Contrast Coherent Population Trapping Resonances Using Four Wave Mixing in 87Rb.

May 15, 2007

Author(s)

V Shah, Svenja A. Knappe, Leo W. Hollberg, John Kitching

We demonstrate a simple technique to generate coherent population trapping (CPT) resonances with very high contrast using four wave mixing in 87Rb atoms. In the experiment, we take advantage of the spectral overlap between F=2 -> F'=2 and F=3 -> F'=2

Differential magnetometry based on a diverging laser beam

March 25, 2007

Author(s)

Eleanor Hodby, Elizabeth A. Donley, John E. Kitching

We discuss a new, compact design for a chip-scale differential atomic magnetometer that uses a single diverging laser beam to both pump and multiply probe the alkali atoms.

Chip scale atomic devices

March 13, 2007

Author(s)

Svenja A. Knappe, P Schwindt, Vladislav Gerginov, V Shah, Alan Brannon, Brad Lindseth, Li-Anne Liew, Hugh Robinson, John Moreland, Z Popovic, Leo W. Hollberg, John E. Kitching

We give an overview over our research on chip-scale atomic devices. By miniaturizing optical setups based on precision spectroscopy, we develop small atomic sensors and atomic references such as atomic clocks, atomic magnetometers, and optical wavelength