University of Colorado

Other

Government of the United States of America, As Represented by the Secretary of Commerce

Long-Sheng Ma

John L Hall

Jun Ye

Henry C Kapteyn

Margaret Mary Murnane

Scott A Diddams

Robert K Shelton

Mark Notcutt

A technique for reducing the vibration sensitivity of laser-stabilizing optical reference cavities is based upon an improved design and mounting method for the cavity, wherein the cavity is mounted vertically. It is suspended at one plane, around the spacer cylinder, equidistant from the mirror ends of the cavity. The suspension element is a collar of an extremely low thermal expansion coefficient material, which surrounds the spacer cylinder and contacts it uniformly. Once the collar has been properly located, it is cemented in place so that the spacer cylinder is uniformly supported and does not have to be squeezed at all. The collar also includes a number of cavities partially bored into its lower flat surface, around the axial bore. These cavities are support points, into which mounting base pins will be inserted. Hence the collar is supported at a minimum of three points.

Mounting system for optical frequency reference cavities

Accurate and efficient synchronization of two pulsed radiation sources (e.g. iwo mode locked lasers) is accomplished in stages. Rough synchronization is accomplished by synchronizing (for example) the fundamental repetition rate of the two lasers. Fine synchronization is accomplished by synchronizing high harmonics of the two lasers. More accurate synchronization may be accomplished by adding more stages, by utilizing light out of a nonlinear laser in which the two beams are crossed, or by utilizing heterodyne beats of the two laser beams. A dc offset signal may added to the control signal generated by the synchronization stages.

Multistage synchronization of pulsed radiation sources

A low-loss comb-generating optical cavity including an optical amplifier and a microwave-driven electro-optic modulator crystal, produces a comb of optical frequency sidebands having spectral lines equally spaced around the frequency of an input laser beam incident on the comb-generating cavity. The comb-generating cavity includes an input mirror movable along the beam propagation direction, and a fixed position output mirror located at time synchronous distances of both the input laser wavelength and modulation wavelength. The comb-generating cavity and its microwave driven modulator are in resonance with the input laser beam, and provide iterative or recirculating beam action that transfers the input optical frequency of the laser, sideband by sideband, to remote and precisely known comb frequencies offset from, and centered on, the input laser frequency. Optical parametric amplification within the comb-generating cavity extends the sideband or comb spectrum and sharpens the time domain impulse represented by the cavity circulating fields. A relatively short bandpass filter optical cavity receives the comb output of the comb-generating cavity and is made up of the fixed-position mirror and a third mirror movable along the beam propagation direction. Fine movement of the third mirror tunes the bandpass filter cavity, and preferentially couples out the power of one or more comb frequencies. An optional input optical cavity at the input side may increase efficiency. A self-oscillating configuration provides optical parametric oscillation.

Comb generating optical cavity that includes an optical amplifier and an optical modulator

Growing community of inventors

Shanghai, China

Long-Sheng Ma