We propose a sub-millimeter-scale vapor-cell atomic-frequency reference based on a micromachined vapor cell, all-optical excitation, and advanced diode-laser technology. We analyze theoretically the performance of such a device as a function of cell size. Initial measurements on small-scale vapor cells support the theoretical treatment.
We provide an overview of our research on chip-scale atomic devices. By miniaturizing optical setups based on precision spectroscopy, we have developed small atomic sensors and atomic references such as atomic clocks, atomic magnetometers, and optical wavelength references. We have integrated microfabricated alkali vapor cells with small low-power lasers, micro-optics, and low-power microwave oscillators. As a result, we anticipate that atomic stability can be achieved with small size, low cost, battery-operated devices. Advances in fabrication methods and performance are presented.
We report on the fabrication of millimeter-sized vapor cells and their performance in atomic clocks based on coherent population trapping (CPT). We discuss two fabrication techniques. The first one is based on hollow-core pyrex fibers, fused with a CO/sub 2/ laser or micro-torch, and the second one involves anodic bonding of micro-machined silicon wafers to pyrex. Key aspects of the discussion are the performance of the cell in frequency references, the potential for further miniaturization of the cells and the ability to manufacture them on a large scale with reproducible performance.
Chip-scale atomic devices combine elements of precision atomic spectroscopy, silicon micromachining, and advanced diode laser technology to create compact, low-power, and manufacturable instruments with high precision and stability. Microfabricated alkali vapor cells are at the heart of most of these technologies, and the fabrication of these cells is discussed in detail. We review the design, fabrication, and performance of chip-scale atomic clocks, magnetometers, and gyroscopes and discuss many applications in which these novel instruments are being used. Finally, we present prospects for future generations of miniaturized devices, such as photonically integrated systems and manufacturable devices, which may enable embedded absolute measurement of a broad range of physical quantities.