Minutes of the ION Washington Section, December 2004

Minutes of the ION Washington Section
Evening Meeting – December 13, 2004

The December Institute of Navigation Washington Section meeting was held at the U.S. Naval Observatory. The meeting had 19 attendees – 12 were ION members and one was a student. The section officers, Jim Doherty (Section Chair), Chuck Schue (Treasurer), Jim Simpson (Program Chair), and Chris Varner (Secretary) all attended.

The agenda of events was the following:

6:00 pm - 6:45 pm Happy Hour
6:45 pm - 7:15 pm Business meeting
7:15 pm - 8:00 pm Speaker: Dr. Svenja Knapp

HAPPY HOUR AND BUSINESS MEETING:

The meeting started in the main building at the US Naval Observatory. People arriving were able to meet one another and sample a variety of appetizers provided by the Section. The displays along the walls describe different cosmological events that can be observed through the Observatory’s telescopes.

Figure 1: Arrival of ION Section Members

During the business meeting attendees were reminded that if they had any ideas for future meeting topics they should mention them to Jim Simpson, our Programs Chair.

LECTURE ON THE CHIP-SCALE VAPOR-CELL ATOMIC CLOCKS:

The briefing given by Dr. Svenja Knappe of The National Institute of Standards and Technology (NIST) in Boulder, CO can be viewed by through the following link.

Briefing on Chip-Scale Vapor-Cell Atomic Clocks

Figure 2: Dr. Svenja Knappe

Precise time and frequency references provide the critical backbone for a wide range of electronic-based systems such as communication networks, data processing devices and global positioning. As electronic devices become increasingly mobile and data rates grow, more stringent demands are being placed on the frequency references that synchronize distributed networks, in terms of both stability and flexibility. The goal of the Chip-Scale Vapor-Lock Atomic Clock Project is to vastly reduce the size and power consumption of an atomic clock to the point where it could be used in a large variety of hand-held, battery-operated instruments such as two-way radios and GPS receivers with much improved tolerance to jamming

The NIST program on chip-scale atomic clocks (CSAC) has developed an atomic clock physics package that displays an improvement over the previous state-of-the-art by a factor of 100 in volume and a factor of 10 in power dissipation. The device demonstrates convincingly that individual components such as microfabricated alkali vapor cells, micro-optics, and semiconductor lasers can be assembled into a compact structure with an output frequency tied to a highly stable atomic transition. With the addition of control circuitry and a local oscillator, it appears feasible to construct a complete atomic frequency reference with a volume below 1 cm3, a power dissipation below 30 mW, and a fractional frequency instability below 10-11 at one hour of integration and longer, allowing timing precision at the microsecond level over a day. Furthermore, the integrated design could be modified to create millimeter-scale atomic magnetometers as well as a variety of other miniaturized spectroscopic tools and sensors.

Our thanks go to Dr. Demetrios Matsakis of the Naval Observatory for helping to coordinate the tour and Dr. Svenja Knappe for giving a thoughtful and interesting presentation.

Figure 3: Thank You Dr. Matsakis

More information regarding Chip-Scale Vapor-Cell Atomic Clock technology can be found at: http://www.boulder.nist.gov/timefreq/ofm/smallclock/index.htm