Research Menu

.
Skip Search Box
Method for Measuring Gain of Photonic Inverters

Aliases:

Optically Controlled Laser, Gain Quenched Laser Logic

Technical Challenge:

When developing or evaluating photonic inverter structures, there is a requirement to measure the minimum gain of the photonic inverters as a metric to quantify performance changes of devices as a function of engineering changes between devices or operational parameters. When the devices under measurement are photonic inverters based upon semiconductor lasers with a side-injection input configuration, the physical geometries of the devices involved do not allow for the direct measurement of the internal photonic input signal power responsible for the quenching function of the photonic inverter. One can easily measure the input power incident upon the device input interface, but to design optimal photonic inverter devices, one needs to quantify the input optical power injected within the active volume of the photonic inverter semiconductor laser cavity which is solely responsible for the gain quenching modulation of the laser output power. The actual power coupled into the laser active region of a photonic inverting device will be less than the total incident input power because of losses associated with scattering, absorption, and transmission. External incident power could be measured with any number of standard optical power measurement techniques but as the associated losses are unknown, the actual power coupled into the photonic inverter laser active region cannot be determined from this measurement. It is this actual power responsible for the quenching interaction that must be accurately characterized for practical design of photonic inverters. Knowledge of the actual power responsible for the quenching of the photonic inverter is required to optimize the design of the actual physical parameters of the photonic inverter device.

Description:

This invention provides a method for measuring the gain of a photonic inverter (change in output signal divided by the change of input signal) by measuring the optical power injected within the active volume of a side-injection input photonic inverter. It provides a measurement method that yields a value for maximum injected optical input power that can be used to evaluate the minimum gain associated with operation of a photonic inverter. The gain of a photonic inverter is measured by determining the input optical signal power using the measured photocurrent induced by the side-injected input optical signal, and the corresponding change in the output power of the photonic inverter is measured by standard techniques.

Demonstration Capability:

A demonstration is not available.

Potential Commercial Application(s):

This method provides knowledge of the actual power responsible for the quenching of a side-injection semiconductor laser photonic inverter. This knowledge is required to optimize the design of the actual physical parameters of the photonic inverter device.

Patent Status:

Issued - United States Patent Number 6,760,350

Reference Number: 1276

If you are interested in exploring this technology further, please express your interest in writing to the:

National Security Agency
NSA Technology Transfer Program
9800 Savage Road, Suite 6541
Fort George G. Meade, Maryland 20755-6541

 

Date Posted: Jan 15, 2009 | Last Modified: Jan 15, 2009 | Last Reviewed: Jan 15 2009

 
bottom